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Introduction

Colloids are a type of mixture in which one material is broken down into tiny particles (known colloidal particles) and spread throughout another. The particles are larger than those found in the solution, yet they are too small to be seen using a microscope. There are no precise size limits for colloidal particles, however, they tend to be in the 10-9m to  10-6m. Preparation of colloids can be done by two methods: dispersion and condensation methods.

What are Colloids?

Colloids are a special kind of mixture in which one substance is dispersed throughout another after being broken down into very small pieces (the “colloidal particles”). Despite being larger than the particles in the solution, they are still too small to be seen with the naked eye.

Colloidal particles can have any size from \({10^9}m\;to\;{10^6}m\) , but typically fall into that range. There are two ways to get colloids ready for use: dispersion or condensation.

Examples of Colloids

Here are several examples of colloids:

• Solid Sols- Pearl, some alloys, gemstones, etc.
• Gels- Gelatin, jelly, etc.
• Aerosols- Fog, clouds, dust, etc.
• Solid Foams- Marshmallows, Styrofoam, etc.
• Emulsions- Milk, lotion, etc.
• Foams- whipped cream, shaving cream, etc.
• Sols- Ink, shampoo, etc.

Classification of Colloids:

Based on Physical State

We can divide colloids into 8 groups:

• Foam
• Emulsion
• Solid aerosol
• Gel
• Solid sol
• Solid foam
• Aerosol
• Sol

Based on Interaction Forces

Lyophilic colloids

Solutions have a colloidal particle size in which the particles of the dispersion phase are evenly distributed and exhibit a high attraction for the dispersed phase known as lyophilic colloids. These sols are quite stable and do not coagulate quickly. Gums, and proteins, along with other lyophilic colloids, are examples.

Lyophobic colloids

Colloidal solutions wherein the dispersed medium particles have no attraction to the dispersion medium are known as lyophobic colloids. For the sake of preservation, these sols require some stabilizing chemicals.

Classification Based on Properties of Sol Particle

Multi Molecular Colloids

When a substance disintegrates, atoms/ molecules clump together to produce colloidal particles. Multimolecular colloids are the particles that result from this process.

Macromolecular Colloids

These are macromolecular colloids, which are macromolecular substances with large molecular sizes that, when broken down, generate a size in the colloids. As a result, the macromolecules that make up the dispersed phase are usually polymers with extremely high molecular weights.

 Based on Dispersion Medium

It can be categorized into four categories based on the dispersion medium:

Preparation of Colloid Solutions:

Condensation method

•  By exchange of solvent,  An S or P solution in alcohol is emptied into \({{\bf{H}}_2}{\bf{O}}\) to form a colloid of  S or P due to its limited water solubility.
•  By change of physical state S or Hg, for example, can be turned into colloidal solutions by transporting their vapours through a stabiliser-laced cold water
• Chemical Methods: Double decomposition: To make \(A{s_2}S\) sol, a constant stream of  \({{\bf{H}}_2}{\bf{S}}\)  gas is fed through such a freezing solution of \(A{s_2}{O_3}\) . This process is continued until the sol’s yellow colour reaches its maximal intensity.
• Oxidation: When \({{\bf{H}}_2}{\bf{S}}\) is passed through \({\bf{S}}{{\bf{O}}_2}\) solution, it forms a colloidal solution.
• \({\bf{2}}{{\bf{H}}_2}{\bf{S}} + {\bf{S}}{{\bf{O}}_2} \to \;{\bf{2}}{{\bf{H}}_2}{\bf{O}} + {\bf{3S}}\)     
•  By excessive cooling:  By freezing a water solution in an organic solvent such as ether/\(CHC{l_3}\), a colloidal ice solution can be created. 

Dispersion Methods

Mechanical dispersion

A colloidal mill is used to grind the solid and liquid together. The colloidal mill is made up of two steel plates that are closely touching and revolving at high speeds in opposite directions. This process is used to create colloidal graphite and printing inks.

Bredig’s Arc Method

Colloids of metals such as gold, platinum, as well as silver can be made using this method. Under the surface of the water with a stabilizing substance, such as a little amount of alkali, an arc is produced between metal electrodes.

Peptisation 

Peptisation is the activity of an electrolyte in a solution to disperse a precipitated substance into a colloidal solution. A peptizing agent is an electrolyte employed.

Purification of Colloids:

Dialysis:

The principle behind dialysis is that colloidal particles cannot flow through parchment or cellophane membranes, but electrolyte ions may. Dialysis is the technique of removing colloidal particles from contaminants by diffusing them through a suitable membrane.

Electro-dialysis:

When an electric field is created between the electrodes, the ions in the electrolyte that are present as impurities diffuse rapidly approaching oppositely charged electrodes. The electric field is needed for this.

Ultrafiltration:

The pores of typical filter paper are large enough to allow both impurities and colloidal particles to pass through. Ultrafilters are the resultant filter sheets. Ultrafiltration is the process of filtering through ultrafilters.

Commercial Applications of Colloid

In pharmacy:

Because colloidal drugs are easily absorbed by biological tissues, they are much more efficacious.

 In environment:

Purification of water: Some electrolytes, like alum, can be employed to precipitate colloidal pollutants in water.

 In industrial products:

Rubber industry: Latex is made up of negatively charged rubber particles suspended in a colloidal fluid. Rubber can be made from latex via coagulation.

In the field of defence:

Colloids are employed in defence in the form of smoke in smoke screens to disguise anything in the military. Colloids are employed in rocket technology. A colloid thruster is used in rockets.

Summary

Colloids, then, are a type of mixture in which one component is spread throughout another substance after being broken down into extremely small particles. Colloidal solutions contain particles of sizes between 1 nanometer and 500 nanometers, which are in between those of a real solution and those of a pure solution. It is typically categorised as a 2-phase, heterogeneous/homogeneous system, depending on the conditions. Colloids are dispersed mixtures in which the suspended particles do not sink to the bottom.

Frequently Asked Questions

1. What is Ultracentrifugation?

Ans. It is the process of using centrifugal force to separate colloidal particles from contaminants. The impure sol is collected in a tube, which is then placed in an ultracentrifuge.

2. Why are the colligative properties of colloids of low order?

Ans. Because colloidal particles are larger aggregates, the particles in colloids are smaller than in a true solution. As a result, when compared to true solution values at similar proportions, measurements of colligative qualities are of low order.

3. What is the Tyndall effect?

Ans. The Tyndall effect confirms the colloidal solution’s heterogeneous character. As light travels through a sol, it is scattered by particles, revealing its route and called the Tyndall effect.

Introduction

A remarkable Mughal empress who showed considerable interest in the political matters of the kingdom was Nur Jahan. She was the 20th wife of Emperor Jahangir. She was a confident and powerful lady who actively took part in Jahangir’s court’s different decision-making processes. The Mughal emperor’s reign was maintained thanks to her bravery and strength. In exchange, she received some honours and benefits that no Mughal empress before or after her ever received.

Early life

Mehr-un-Nissa was the actual name of Nur Jahan. She was born in Afghanistan’s present capital city of Kandahar. Mirza Ghiyas Beg and his wife Asmat Begum welcomed their fourth child, Nur Jahan, into the world in 1577. They belonged to an Iranian noble household. Mirza Ghiyas Beg travelled to India in quest of work after experiencing some financial difficulties. Nur Jahan was able to resume her education due to his efforts to make sure of it. In addition to studying the arts, ballet, music, and writing, she was a prodigy in languages like Arabic and Persian.

Mughal Empress Nur Jahan

First Marriage of Nur Jahan

In 1594, at the age of 17, Mehr-un-Nissa wed Sher Afgan Khan. Under the rule of kings Akbar and Jahangir, Sher Afgan Khan led the Mughal military. Mehr-un-Nissa and Sher Afgan Khan were graced with a daughter in 1605, whom they called Ladli Begum. Sher Afgan was assassinated in 1607, two years after Jahangir had succeeded to the Mughal empire, amid numerous rumours. One of these rumours suggested that Jahangir may have personally planned the murder of Sher Afgan. 

After he passed away, Ruqaiya Sultan Begum, the widow of the late Emperor Akbar, hired Nur Jahan and her daughter to serve as “ladies-in-waiting” at the court of Jahangir for security.

Marriage of Nur Jahan to Jahangir

Jahangir and Nur Jahan were wed in 1611 at the spring celebration of Nowroz, where Jahangir first met Nur Jahan in the Meena bazaar. As soon as he saw her, he proposed, and they were wedded the following year, to Nur Jahan. Jahangir, who was enamoured with her attractiveness, gave her the names “Nur Mahal” and “Nur Jahan,” respectively, which mean “light of the palace” and “light of the globe,” to describe her.

Jahangir valued her view on the state’s political matters because he respected her so much. The Mughal empire’s most powerful and prestigious emblem of resolve was even given to her—his royal insignia. With the support of this seal, she was able to look over and authorize any request before it gained legality. Her name was inscribed on coins for the first time; no other Mughal queen had ever experienced this.

Jahangir and Prince Khurram with Nur Jahan 

Mughal Empress

She was also a great defender of the Mughal kingdom, securing the borders, settling family conflicts, and quelling uprisings. She even came up with an answer when a conflict arose over the name of the empire’s next ruler when Jahangir was not present. She used her cunning and strength to free Jahangir in 1626 after Mahabat Khan, the rebel leader, had kidnapped him.

According to historians, Nur Jahan once served as a representative of Jharokhas, where she welcomed crowds, at the palace of Jahangir. Nur Jahan used to issue orders and take the risk of using her power when Jahangir was ill and addicted. Nur Jahan’s use of governmental authority established a precedent.  She was an excellent hunter who treasured going hunting with Jahangir.

Life of Nur Jahan after Jahangir’s death

Nur Jahan and her daughter were placed under house arrest in Lahore after Jahangir died as a result of a plot by her brother, the subsequent successor, Shah Jahan. She was in charge of overseeing construction of Itmad-ud-mausoleum Daula’s in Agra at this period. According to historians, the Taj Mahal was modelled after this mausoleum.

Summary

Nur Jahan was an extraordinary Mughal empress who left an imprint on Mughal history. She played a pivotal role when Jahangir was present and took policy decisions when he was ill. Not only was she beautiful, but she also had a keen interest in the state affairs of the Mughal empire. She participated actively in the court proceedings when the emperor Jahangir was present. When Jahangir used to be ill and died, Nur Jahan took over the court affairs. As Jahangir trusted her immensely, he made it necessary to take the consent of Nur Jahan while approving any order. He even minted a coin imprinting her name on it and gave her the prestigious imperial seal. 

Frequently asked question

1. Describe in brief about Nur Jahan’s personality.

Nur Jahan was a smart and beautiful lady. She was a lady of culture, intelligence, and education. In addition to her intense interest in state politics, she also had a keen interest in fashion. She was able to take on state matters and stood strongly by the oppressed and underprivileged people thanks to her problem-solving skills, bravery, resilience, generosity, and kind spirit.

2. What was the Nur Jahan Junta?

Following her marriage, Nur Jahan established a tight circle of friends, including herself, her father Itimad-ud-Daula, mother Asmat Begum, and prince Khurram. The Nur Jahan Group was the name of this organisation. Each member had better positions within the Mughal kingdom and was competent.

3. Why did Nur Jahan have such control in Jahangir’s court?

Nur Jahan was unquestionably extremely talented and charismatic, which is likely why she was capable of holding as much control as she did.

 

प्रत्यय दो शब्दों से मिलकर बना है, ‘प्रति’ और ‘अय।’ प्रति का अर्थ है साथ में, लेकिन अंत में और अय का अर्थ है चलने वाला। इसलिए प्रत्यय का अर्थ है साथ में लेकिन अंत में चलने वाला। वे शब्द जो किसी अन्य शब्द के अंत में जुड़कर अपनी प्रकृति के अनुसार शब्द का अर्थ बदल देते है, उसे प्रत्यय कहते है। यह शब्द किसी शब्द के अंत में लगाए जाते है। इनका अपना कोई अर्थ नहीं होता है और न ही ये स्वंतत्र शब्द होते हैं।

प्रत्यय के प्रयोग से मूल शब्द के अनेक अर्थों को प्राप्त किया जा सकता है। यौगिक शब्द बनाने में प्रत्यय का महत्त्वपूर्ण स्थान है, इसलिए प्रत्यय भाषा में महत्वपूर्ण है।

प्रत्यय को मुख्य तीन भागों में बाँटा गया है–:

1. हिंदी के प्रत्यय
2. संस्कृत के प्रत्यय
3. उर्दू के प्रत्यय

1. हिंदी के प्रत्यय

हिंदी के प्रत्यय के दो भेद है–

• कृत प्रत्यय
• तद्धित प्रत्यय

1.कृत प्रत्यय-:

कृत प्रत्यय वह प्रत्यय जो क्रिया पद के मूल रूप के साथ लगकर एक नए शब्द का निर्माण करते हैं। कृत प्रत्यय से मिलकर जो प्रत्यय बनते हैं, उन्हे कृदंत प्रत्यय कहते हैं। यह प्रत्यय क्रिया और धातु को एक नया अर्थ देते हैं। 

उदाहरण के लिए 

लेखक, गायक –: दिए गए शब्द के मूल रूप के अंत में ‘एक’ प्रत्यय लगाया गया है। जिससे क्रिया पद लेख और गाय के मूल रूप में परिवर्तन हो गया है।

लुटेरा, बसेरा–: दिए गए शब्द के मूल रूप के अंत में ‘एरा’ प्रत्यय लगाया गया है। जिससे क्रिया पद लूट और बस के मूल रूप में परिवर्तन हो गया है।

तैराक, लड़ाक –: दिए गए शब्द के मूल रूप में  अंत में आक प्रत्यय लगाया गया है। जिससे क्रिया पद तैर और लड़ के मूल रूप में परिवर्तन हो गया है।

लटकाई, चढ़ाई –: दिए गए शब्द के मूल रूप में आई प्रत्यय लगाया गया है। जिससे क्रिया पद उसके लटक और चढ़ के मूल रूप में परिवर्तन हो गया।

कृत प्रत्यय के भेद–;

1. कृत् वाचक
2. कर्म वाचक
3. करण वाचक
4. भाव वाचक
5. क्रिया वाचक

(1) कृत् वाचक 

कर्ता का बोध कराने वाले प्रत्यय कृत् वाचक प्रत्यय कहलाते है। 

उदाहरण –

हार पालनहार, राखनहार

वाला रखवाला, लिखनेवाला

क रक्षक, शोषक

अक लेखक, गायक, नायक

ता दाता, माता,  नाता

इन सभी प्रत्यय से कर्ता का बोध होता है।

(2) कर्म वाचक कृत् प्रत्यय 

कर्म का बोध कराने वाले कृत् प्रत्यय कर्म वाचक कृत् 

प्रत्यय कहलाते हैं।

उदाहरण – 

औना खिलौना, बिछौना

नी ओढ़नी, मथनी, छलनी

ना पढ़ना, लिखना, गाना

इन सभी प्रत्यय से कर्म या काम का बोध होता है।

(3) करण वाचक कृत् प्रत्यय 

साधन का बोध कराने वाले कृत् प्रत्यय करण वाचक कृत प्रत्यय कहलाते हैं।

 उदाहरण –

अन पालन, सोहन

नी चटनी,  

ऊ  झाडू, चालू

ई खाँसी,  फाँसी

(4) भाव वाचक कृत् प्रत्यय 

क्रिया के भाव का बोध कराने वाले प्रत्यय भाववाचक कृत् प्रत्यय कहलाते हैं।

 उदाहरण –

आप मिलाप, विलाप

आवट सजावट, मिलावट, लिखावट

आव खिंचाव, तनाव

आई लिखाई, खिंचाई, चढ़ाई

(5) क्रियावाचक कृत् प्रत्यय 

क्रिया शब्दों का बोध कराने वाले कृत् प्रत्यय क्रिया वाचक कृत प्रत्यय कहलाते हैं

 उदाहरण –

या आया, बोया, खाया

कर गाकर,  सुनकर

आ सूखा, भूला

ता पीता, लिखता

2. तद्धित प्रत्यय 

वह शब्द जो क्रिया को छोड़कर संज्ञा, सर्वनाम, विशेषण आदि शब्दों में अंत में जोड़े जाते हैं तथा एक नए शब्द की रचना करते हैं, उन शब्दांश को तद्धित प्रत्यय कहते हैं। तध्दित प्रत्यय आठ प्रकार के होते है।

उदाहरण –: आत्मजा, छात्रा । इसमें आत्मजा और सर्वनाम छात्रा में आ प्रत्यय लगाया गया है।

मिठास, खट्टास–: इन विशेषणों में आस प्रत्यय लगाया गया है।

अपनापन, पागलपन –: इन शब्दों में पन प्रत्यय लगाया गया है।

बुराई, खुदाई–: इन शब्दों में आई प्रत्यय लगाया गया है।

तद्धित प्रत्यय के भेद 

1. कर्तृवाचक तद्धित प्रत्यय
2. भाववाचक तद्धित प्रत्यय
3. सम्बन्ध वाचक तद्धित प्रत्यय
4. गुणवाचक तद्धित प्रत्यय
5. स्थानवाचक तद्धित प्रत्यय
6. ऊनतावाचक तद्धित प्रत्यय
7. स्त्रीवाचक तद्धित प्रत्यय

(1) कर्तृवाचक तद्धित प्रत्यय 

कर्ता का बोध कराने वाले तद्धित प्रत्यय कर्तृवाचक तद्धति प्रत्यय कहलाते हैं।

उदाहरण –

आर लुहार, कुम्हार

ई माली, तेली

वाला गाङीवाला, टोपीवाला,

(2) भाववाचक तद्धित प्रत्यय 

भाव का बोध कराने वाले तद्धित प्रत्यय भाववाचक तद्धित प्रत्यय कहलाते हैं।

 उदाहरण –

आहट कङवाहट

ता सुन्दरता, मानवता, दुर्बलता

आपा मोटापा, बुढ़ापा, बहनापा

ई गर्मी, सर्दी, गरीबी

(3) सम्बन्ध वाचक तद्धित प्रत्यय 

सम्बन्ध का बोध कराने वाले तद्धित प्रत्यय सम्बन्ध वाचक तद्धित प्रत्यय कहलाते हैं।

उदाहरण –

इक शारीरिक, सामाजिक, मानसिक

आलु कृपालु, श्रद्धालु, ईर्ष्यालु

ईला रंगीला, चमकीला, भङकीला

तर कठिनतर, समानतर, उच्चतर

(4) गुणवाचक तद्धित प्रत्यय 

गुण का बोध कराने वाले तद्धित प्रत्यय गुणवाचक तद्धित प्रत्यय कहलाते हैं

 उदाहरण –

वान गुणवान, धनवान, बलवान

ईय भारतीय, राष्ट्रीय, नाटकीय

आ सूखा, रूखा, भूखा

ई क्रोधी, रोगी, भोगी

(5) स्थानवाचक तद्धित प्रत्यय 

स्थान का बोध कराने वाले तद्धित प्रत्यय स्थानवाचक तद्धित प्रत्यय कहलाते हैं।

 उदाहरण –

वाला शहरवाला, गाँववाला, कस्बेवाला

इया उदयपुरिया, जयपुरिया, मुंबइया

ई रूसी, चीनी, राजस्थानी

(6) ऊनतावाचक तद्धित प्रत्यय 

लघुता का बोध कराने वाले तद्धित प्रत्यय ऊनतावाचक तद्धित प्रत्यय कहलाते हैं।

जैसे –

इया लुटिया

ई प्याली, नाली, बाली

ङी चमङी, पकङी

ओला खटोला, संपोला, मंझोला

(7) स्त्रीवाचक तद्धित प्रत्यय 

स्त्रीलिंग का बोध कराने वाले तद्धित प्रत्यय स्त्रीवाचक तद्धित प्रत्यय कहलाते हैं।

 उदाहरण –

आइन पंडिताइन, ठकुराइन

इन मालिन, कुम्हारिन, जोगिन

नी मोरनी, शेरनी, नन्दनी

आनी सेठानी, देवरानी, जेठानी

2. संस्कृत प्रत्यय 

हिंदी भाषा में संस्कृत के प्रत्यय भी प्रयोग किया जाए हैं।

इत गर्वित, लज्जित, 

इक मानसिक, धार्मिक, , पारिश्रमिक

ईय भारतीय,  राष्ट्रीय, स्थानीय

एय पाथेय, राधेय, कौंतेय

तम अधिकतम, महानतम, श्रेष्ठतम

वान् बलवान, गुणवान, दयावान

मान् शक्तिमान, बुद्धिमान

त्व लघुत्व, बंधुत्व, नेतृत्व

शाली वैभवशाली, गौरवशाली, प्रभावशाली

तर श्रेष्ठतर, उच्चतर, लघूत्तर

3. उर्दू के प्रत्यय

भाषा का हिन्दी के साथ लम्बे समय तक प्रचलन में रहने के कारण हिन्दी भाषा में उर्दू भाषा प्रत्यय भी प्रयोग में आने लगे हैं।

जैसे –

गी ताजगी, बानगी, सादगी

गर कारीगर, बाजीगर, सौदागर

ची नकलची, तोपची, अफीमची

दार हवलदार, जमींदार, किरायेदार

खोर आदमखोर, चुगलखोर, रिश्वतखोर

गार खिदमतगार, मददगार, गुनहगार

नामा बाबरनामा, जहाँगीरनामा, सुलहनामा

बाज धोखेबाज, नशेबाज, चालबाज

मन्द जरूरतमन्द, अहसानमन्द, अकलमन्द

आबाद सिकन्दराबाद, औरंगाबाद, मौजमाबादइन्दा – बाशिन्दा, शर्मिन्दा, परिन्दा

इश साजिश, ख्वाहिश, फरमाइश

गाह ख्वाबगाह, ईदगाह, दरगाह

गीर आलमगीर, जहाँगीर, राहगीर

आना नजराना, दोस्ताना, सालाना

इयत इंसानियत, खैरियत, आदमियत

ईन शौकीन, रंगीन, नमकीन

कार सलाहकार, लेखाकार, जानकार

दान खानदान, 

अधिकतर पूछें गए प्रश्न–:

1.प्रत्यय किसे कहते है?

उत्तर:  वे शब्द जो किसी अन्य शब्द के अंत में जुड़कर अपनी प्रकृति के अनुसार शब्द का अर्थ बदल देते है उसे प्रत्यय कहते है। यह शब्द किसी शब्द के अंत में लगाए जाते है। इनका अपना कोई अर्थ नहीं होता है और न ही ये स्वंतत्र शब्द होते हैं।

2.प्रत्यय के कितने भेद होते हैं?

उत्तर: प्रत्यय को मुख्य तीन भागों में बांटा गया है–:

1.हिन्दी के प्रत्यय

2. संस्कृत के प्रत्यय
3. उर्दू के प्रत्यय

3. “कृत प्रत्यय” किसे कहते हैं ?

उत्तर: कृत प्रत्यय, वह प्रत्यय जो क्रिया पद के मूल रूप के साथ लगकर एक नए शब्द का निर्माण करते हैं। कृत प्रत्यय से मिलकर जो प्रत्यय बनते हैं, उन्हे कृदंत प्रत्यय कहते हैं। यह प्रत्यय क्रिया और धातु को एक नया अर्थ देते हैं। 

4.तद्धित प्रत्यय किसे कहते हैं ?

उत्तर: वह शब्द जो क्रिया को छोड़कर संज्ञा, सर्वनाम, विशेषण आदि शब्दों के अंत में जोड़े जाते हैं तथा एक नए शब्द की रचना करते हैं, उन शब्दांश को तद्धित प्रत्यय कहते हैं। तद्धित प्रत्यय आठ प्रकार के होते है।

5. हिंदी के प्रत्यय के कितने भेद होते हैं?

उत्तर: हिंदी के प्रत्यय के दो भेद होते हैं

1.कृत प्रत्यय

2. तद्धित प्रत्यय

सर्वनाम	संज्ञा
प्रत्यय	अलंकार
वर्तनी	पद परिचय
वाक्य विचार	समास
लिंग	संधि
विराम चिन्ह	शब्द विचार
अव्यय	काल

उपसर्ग दो शब्दों ‘उप’ और ‘सर्ग’ से जुड़कर बना हुआ है। उपसर्ग का अर्थ है किसी शब्द के पास आ कर नया शब्द बनाना।

उपसर्ग किसी भी शब्द के आरंभ में लगाया जाता है, जिससे उस शब्द का अर्थ बदल जाता है और एक नया शब्द बनता है। उपसर्ग किसी शब्द के आरंभ में जुड़ने पर उसका अर्थ बदल देता है। 

उपसर्ग का खुद का एक अर्थ होता है जो उस शब्द के अर्थ को बदल देता है।एक उपसर्ग का एक से अधिक अर्थ भी निकल सकता है। यह जुड़ने वाले शब्द पर निर्भर करता है कि वह किस तरह किसी बात को प्रस्तुत करता है।

उदाहरण – आ + हार = आहार

इस शब्द में ‘हार’ का अर्थ है ‘आभूषण’ लेकिन इसके आगे ‘आ’ उपसर्ग जोड़ने से इसका अर्थ खाने के भोजन में बदल जाता है। इस प्रकार उपसर्ग लगने से शब्द का अर्थ बदल जाता है।

अप + मान = अपमान 

इस शब्द में ‘मन’ का अर्थ है ‘सम्मान’ लेकिन इसमें ‘अप’ उपसर्ग लगा हुआ है, जिससे यह ‘अपमान’ बन गया जिसका अर्थ है सम्मान न करना या बेइज्जती।

आ + दान = आदान

इस शब्द में ‘दान’ का अर्थ है किसी वस्तु को देना लेकिन ‘आ’ उपसर्ग को इसमें जोड़कर इसका अर्थ बदलकर किसी वस्तु को लेना बन गया है, जिससे इसका वास्तविक अर्थ बदल गया।

प्रति + वर्ष = प्रतिवर्ष

इस शब्द ‘वर्ष’ को ( कोई भी वर्ष ) विशेष वर्ष नहीं बताया गया है, लेकिन ‘प्रति’ उपसर्ग लगाकर प्रत्येक वर्ष ले रूप में अंकित कर दिया गया है। प्रति का अर्थ होता है प्रत्येक।

वि+ धायक = विधायक।

इस शब्द में ‘वि’ उपसर्ग धायक शब्द के साथ जोड़ा गया है जिससे एक नया शब्द और एक नया अर्थ निकलकर आ रहा है और पुराना अर्थ और पुराना शब्द लुप्त हो गया है।

उपसर्ग के तीन प्रकार होते हैं

1) संस्कृत उपसर्ग

 जिनकी संख्या 22 है।

अति, अधि, अनु, अप, अभि, अव, आ, उत्, उप, दुर, नि, परा, परि, प्र, प्रति, वि, सम्, सु, निर्, दुस्, निस्, अपि।

2) हिंदी उपसर्ग 

इनकी संख्या 10 है।

अ, अध, ऊन, औ, दु, नि, बिन, भर, कु, सु।

3) उर्दू उपसर्ग 

इनकी संख्या 19 है।

अल, ऐन, कम, खुश, गैर, दर, ना, फ़िल्, ब, बद, बर, बा, बिल, बिला।

1)संस्कृत उपसर्ग

अति, अधि, अनु, अप, अभि, अव, आ, उत्, उप, दुर, नि, परा, परि, प्र, प्रति, वि, सम्, सु, निर्, दुस्, निस्, अपि ।

अति –  अतिशय, ( अति का अर्थ अधिक होता है)

अधि – अधिपति, अध्यक्ष ,अध्यापन

अनु –  अनुक्रम, अनुताप, अनुज;  अनुकरण, अनुमोदन.

अप – अपकर्ष, अपमान; अपकार, अपजय.

अपि –  अपिधान 

अभि –  अभिनंदन, अभिलाप अभिमुख, अभिनय

अव – अवगणना, अवतरण;अवगुण.

आ – आगमन, आदान; आकलन.

उत् –  उत्कर्ष, उत्तीर्ण, 

उप –  उपाध्यक्ष, उपदिशा; उपग्रह, उपनेत्र

दुर्,  दुस् –  दुराशा, दुरुक्ति, 

नि – निमग्न, निबंध निकामी, 

निर् – निरंजन, निराषा

निस् –निष्फळ, निश्चल, 

परा (परा का अर्थ कमी होता है) – पराजय, 

परि – परिपूर्ण,परिश्रम, परिवार

प्र –  प्रकोप,  प्रबल

प्रति – प्रतिकूल, प्रतिच्छाया,  प्रतिदिन, प्रतिवर्ष, प्रत्येक ( प्रति का अर्थ प्रत्येक या हर एक होता है।)

वि –  विख्यात,  विवाद,  विफल, विसंगति (वि का अर्थ अधिक होता है।)

सम् –  संस्कृत, संस्कार, संगीत, संयम, संयोग, संकीर्ण.

सु – सुभाषित, सुकृत, सुग्रास; सुगम, सुकर, स्वल्प;

सु – (अधिक) सुबोधित, सुशिक्षित।

एक उपसर्ग के एक से अधिक अर्थ भी होते है। यह नियम उसके साथ जुड़ने वाले शब्द पर निर्भर करता है कि वह किस अर्थ के रूप में उस से जुड़ रहा है।

ये सभी उपसर्ग है जो शब्द के आरंभ में लगाए गए है। इनके प्रयोग से शब्द का वास्तविक अर्थ बदल गया है और एक नया अर्थ उत्पन्न हुआ है।

2)हिंदी उपसर्ग–:

अ, अध, ऊन, औ, दु, नि, बिन, भर, कु, सु।

अ – अनेक

ऊन – उन्नति

अध – अधूरा, अधम

दु – दुश्मन, दुष्प्रभाव

नि – निर्भय, निराला

भर– भरपूर, भरा ( भर का अर्थ पूरा या भरा हुआ होता है)

कु – कुकर्म, कुशलता (कुकर्म में कु उपसर्ग गलत अर्थ हो दर्शाता है जबकि कुशलता अर्थ में कु उपसर्ग अच्छी और निपुणता को दर्शाता है) 

सु – सुस्वागत, सुइच्छा ( सु का अर्थ अच्छा होता है)

इस प्रकार शब्द के आरंभ में हिंदी के उपसर्ग को लगाया जाता है। यह उपसर्ग लगाने के बाद शब्द के मूल अर्थ में परिवर्तन आ जाता है।

3)उर्दू-फारसी के उपसर्ग –:

अल, ऐन, कम, खुश, गैर, दर, ना, फ़िल्, ब, बद, बर, बा, बिल, बिला।

अल – अलविदा, अलबत्ता

कम – कमसिन, कमअक्ल, कमज़ोर

खुश – खुशबू, खुशनसीब, खुशकिस्मत, खुशदिल, खुशहाल, खुशमिजाज

ग़ैर ( गैर का अर्थ किसी चीज की मनाही होता है)-  ग़ैरहाज़िर ग़ैरकानूनी ग़ैरवाजिब ग़ैरमुमकिन ग़ैरसरकारी,  ग़ैरमुनासिब

दर – दरअसल दरहकीकत

ना – (अभाव) – नामुमकिन नामुराद नाकामयाब नापसन्द नासमझ नालायक नाचीज़ नापाक नाकाम

फ़ी – फ़ीसदी फ़ीआदमी

ब – बनाम, बदस्तूर , बमुश्किल , बतकल्लुफ़

बद – (बुरा)- बदनाम , बदमाश, बदकिस्मत,बददिमाग, बदहवास, बददुआ,

बर – (पर,ऊपर, बाहर) – बरकरार, बरअक्स ,बरजमां

बा – ( बा का अर्थ सहित होता है) – बाकायदा, बाकलम, बाइज्जत, बाइन्साफ, बामुलाहिजा

बिला -(बिला का अर्थ बिना होता है)- बिलावज़ह, बिलालिहाज़ 

बे – (बे का अर्थ बिना/ नहीं होता है) – बेबुनियाद , बेईमान , बेवक्त , बेरहम बेतरह बेइज्जत , बेअक्ल , बेकसूर,  बेमानी,  बेशक

ला -( ला का अर्थ बिना, नहीं होता है) – लापता , लाजबाब,  लावारिस लापरवाह।

इस प्रकार उर्दू के उपसर्गों को शब्दों के आरंभ में जोड़कर एक नया शब्द बनाया जाता है। जिससे पुराने शब्द का अर्थ बदल जाता है।

प्रत्यय – परिभाषा, भेद और उदाहरण

अधिकतर पूछें गए प्रश्न–:

 1.उपसर्ग का प्रयोग कहाँ होता है?

उत्तर: उपसर्ग का प्रयोग शब्द के आरंभ में किया जाता है। जिसमें उपसर्ग के प्रयोग से वास्तविक शब्द का अर्थ बदल जाता है।

2.हिंदी में उपसर्ग के कितने भेद है?

उत्तर: व्याकरण में उपसर्ग को तीन भागों में बाँटा गया है, जिसमें हिंदी में उपसर्ग के 10 भेद है।

अ, अध, ऊन, औ, दु, नि, बिन, भर, कु, सु।

3. ‘पराक्रम’ में कौन-सा उपसर्ग है?

उत्तर: ‘पराक्रम’ में ‘परा’ उपसर्ग लगाया गया है। इसमें ‘क्रम’ शब्द का अर्थ है ‘अंक’ लेकिन पराकर्म का अर्थ है शक्तिशाली। इसमें उपसर्ग लगाकर वास्तविक अर्थ को बदल दिया गया है।

4.संस्कृत में उपसर्ग के कितने भेद है?

उत्तर: व्याकरण में उपसर्ग के तीन भेद है जिसमे से संस्कृत में उपसर्ग के 22 भेद है।

अति, अधि, अनु, अप, अभि, अव, आ, उत्, उप, दुर, नि, परा, परि, प्र, प्रति, वि, सम्, सु, निर्, दुस्, निस्, अपि।

5. अनुग्रह में कौन सा उपसर्ग है?

उत्तर: अनुग्रह में अनु उपसर्ग है। इसमें उपसर्ग लगाकर वास्तविक शब्द ग्रह का ही अर्थ बदल दिया है। उपसर्ग शब्द के आरंभ में लगाए जाते हैं।

इन्हे भी पढ़िये

सर्वनाम	संज्ञा
प्रत्यय	अलंकार
वर्तनी	पद परिचय
वाक्य विचार	समास
लिंग	संधि
विराम चिन्ह	शब्द विचार
अव्यय	काल

Introduction

The poem Keeping Quiet by Pablo Neruda emphasizes the importance of peace and silence everywhere. It mainly focuses on maintaining tranquility in our environment as he is bothered about harming animals, the bitterness amongst the humans or man made wars. He has tried to portray his subdued expression of peace by inciting some beautiful examples in the entire poem.

Summary of the Poem

The poem have highlighted  a very important and  major issue surrounding us and it’s about silence and peace. The poet wanted everyone to wait till the clock ticks 12 in the clock and after that all will go fo silence for some time for  self contemplation. As we have stopped bothering about brotherhood, maintain peace and harmony amongst the animals and we have turned into selfish giants.

Keeping peace

At the beginning there will be a feeling of little weirdness  as everything  will come to a halt for  while. There will be no buzzing and annoying sounds of the engines, no one will be speaking in different languages and be quiet for a moment. But this calmness and silence can bring us together and can connect us to  one common place which the poet has tried to mention as an exotic moment. The exotic moment is none other than the happiness that everyone will feel after this silence.

The middle of the poem clarifies that how there will b no activity in the sea as it will turn totally cold due to this silence and fishermen will not be able to harm aquatic animals like W Hales any more. The people involved in collecting salt from the sea will not be hurting their hands anymore for this stillness posed in the poet’s mind.

At the end the poet has described beautifully the essence of brotherhood and together ness by mentioning that there will be no green wars by using gases and hence the men doing that will be freed of this wrongdoing and rather will it on clean clothes. By this they will survive happily with their brothers and a state of tranquility and calmness will be be prevailing everywhere around the World.

Conclusion

“Keeping Quiet” points out the significance of peace and silence and that these can bring about happiness amongst everyone. The poet has cited quite a few examples like no harming of animals or no green wars can prevail the essence of brotherhood and companionship amongst all men in the World. He even tried to stop the annoying engine noises so that everywhere it can be calm and men can think about togetherness.

About the poet

Pablo Neruda (1904–1973) was a noteworthy Chilean poet and  a true politician who used a pen name besides using his real name. He received the Nobel Prize for Literature in the year 1971.His writings are uncomplicated and reader friendly. The essence of this poem, which was originally written in Spanish, is mainly focused on introversion about peace and silence.

 

Textbook Question and Answers

1. What can Humans learn from this poem about nature?

Ans: Our Mother Earth can teach a lot of examples that will help us restore humanity and peace aeverywhere.Humans should learn how to maintain brotherhood and calmness everywhere by not harming animals or humans and not conducting wars.

2. What is the literal meaning of ‘total inactivity’? 

Ans:-Pablo Neruda meant by saying total inactivity that inactivity in the sea can make it cold and as a result there will be no harm caused to the aquatic animals like Whales and no men can collect from the sea any more.

3. Why does the poet seem sad in the poem?

Ans:-The sadness of the poet mainly revolves around the inhuman that is prevailing everywhere amongst the humans.They have forgotten about brotherhood and have become selfish and thinks and care about themselves rather than helping others.They will rather harm others for their own peace.

4. Why do you think that the poet has used the word “Total Inactivity”?

Ans:-Pablo Neruda wanted to promote humanity and peacefulness as they have forgot about the mankind and go on to be selfish .So he wants that one day if everything comes to stillness, rather in the form of inactivity for a few moments happiness can be spread amongst the entire World.

Extra Question Answers

1.Do you feel that there is a glimpse of sadness in the poem?

Ans:-Yes, the poem signifies sadness as the poet is really worried about the present situation of mankind. According to the poet man has forgotten about brotherhood and has become selfish and thinks and cares about himself rather than helping others.They will rather harm others for their own peace.

2.What does “green war” signify?

Ans:-Green wars signify no use of gases and fires in the wars,which also signifies a clarion call to the entire humanity about their harmful and selfish nature due to which they have forgotten about the essence of brotherhood. They are busy themselves to create wars and spread brutalism everywhere.

3. What is the meaning of exotic moment in the poem?

Ans:-Pablo Neruda longed for  exotic moment when the entire mankind will be free from selfishness, brutality and inhuman actions. Unnecessary rush and noise have caused unpleasantness and troubles. The poet wishes the  annoying noise of engines and machines should come to an end and then only tranquility might prevail.

4. How will stopping for a second can help mankind ?

Ans:-According to Pablo Neruda, if we stop for  second there will be little strange ness for while but there will be no buzzing and annoying sounds of the engines,no one will be speaking in different languages and be quiet for a moment.But this calmness and silence can bring us together and can connect us to  one common place which the poet has tried to mention as an exotic moment.

Introduction

The author of “My Mother at Sixty-Six”, “Kamala Das”, is renowned for depicting the complexity of “human relationships”. The poem is one of the best representations of a human connection, especially between a “mother and daughter”.  It expresses the poet’s suffering and fear of losing her mother as a result of the terrible fact of life, which is death.

Short Summary

 In this poem, the poet expresses her affection and attachment to her aging mother 

The poet once went to see her mother. She was returning to the airport to fly back to Cochin. She turned to face her mother in the passenger seat of the car. Her mother had fallen asleep, and the color of her aging face was ashy-smoky. She looked like a dead person since her mouth was open. The poet became aware of her mother’s advanced age. She sympathized with her and sensed her pain. Her mother needs devotion, care, and love.

The poet turned her head to look out the car window to escape the darkness. She observed young trees passing by there. Little kids were rushing into the playgrounds from their homes. These things stood in stark contrast to her mother’s aging face. 

The poet looked at her mother one more time when they arrived at the airport and she was going to board the plane. Like the moon in the winter, which seems to have lost all of its strength, her mother looks frail and pale. The loss of her mother caused the poet both pain and fear. She recalled her early years when she used to worry about losing her mother. She struggled as a child to tolerate even brief periods of separation from her mother. Now that her mother was on the verge of passing away, the loss would be irreparable.

The poet kept her emotions to herself. To ensure that her mother would live and that they may one day reunite, she smiled and added, “See you soon, Amma.”

Mother-daughter

About the poet

The poet Kamala Das also published works under the pen name “Madhavikutty.” She was one of India’s first poets and was born in Kerala. Her topic reflects her personality, which is stunning, tender, brave, and troubled.

Conclusion

The poem conveys a message that it is a slow but inevitable realization that one’s parents are aging. Parents are young and capable when one is growing up, but they age in front of our eyes. Here, the poet expresses sadness over learning the same thing about her mother. The advice is to spend more time with them.

My Mother at Sixty Six – Textbook Question and Answers

1. What is the kind of pain and ache that the poet feels?

Ans: The poet feels a familiar sorrow or aches when she sees her mother’s pale and lifeless face. Perhaps she has been afraid of this since she was young. Growing older is a normal process. “Ageing and time” have no mercy. The poet’s mother has not been spared by time or aging, and she might not be. Death and separation are “inevitable” as we age.

2. Why are the young trees described as ‘sprinting’?

Ans: The poet travels by car to “Cochin  Airport”. When she glances outdoors, it appears the young trees are moving by them. They appear to be running quickly or sprinting at the pace of the car. Her elderly mother, who is “dozing,” and the youthful trees, who are “sprinting,” are contrasted by the poet.

3. Why has the poet brought in the image of the merry children ‘spilling out of their homes?

Ans: The poet used the metaphor of the happy kids “spilling out of their homes” to create contrast. The jubilant children who are streaming out of their homes in large numbers are the ones who can best describe life’s freshness and joy. It contrasts with the elderly mother who is “dozing,” whose “ashen” face is “pale and lifeless”, like a corpse. The poet’s mother is described throughout the poem in a way that strongly suggests inactivity, degradation, and aging. The contrast between these two pictures enhances the poem’s impact.

4. Why has the mother been compared to the ‘late winter’s moon’? 

Ans: The mother of the poet is “66 years old”. Her ‘ashen’ shrunken face looks like a corpse. She no longer possesses the brightness and energy of youth. The moon in the dead of winter appears similarly “foggy and opaque”. It also lacks luster and durability. The connection is quite appropriate and natural. Here, the metaphor is both relevant and powerful.

5. What do the parting words of the poet and her smile signify?

Ans: When compared to the childhood terror or familiar ache, the poet’s leaving words of confidence and her smiles stand in stark contrast. She makes a conscious effort to conceal her true emotions through her words and smiles. The elderly woman, whose “ashen face” appears to be that of a corpse, is comforted by the parting words, “See you soon, Amma.” Similar to this, her continuous smiles are an effort to get over the pain and terror inside her heart.

Extra Questions

1. What was the poet’s greatest fear as a child? 

Ans: The young child always worries about losing his parents. The poet’s fear growing up was similar to that of losing her mother or her companionship.

2. Why did the poet continue to smile?

Ans: The poet smiled frequently to remind herself that she would soon meet her mother. She makes a conscious effort to mask her true concerns and emotions with her words and smiles.

3. What painful realizations did the poet have?

  Ans: The poet’s mother’s lifeless and faded face hurts her heart. She appears dead, like a corpse. She paints a picture of slowness, degradation, and death. The elderly woman appears to be deep in her thoughts.

4. In the poem, what is “wan and pale”?

Ans: Wan: feeble and dim. Pale:  without color. The poet goes on to say that after arriving at the airport, she completed the security check and then stood close to her mother. She observed how her mother’s aging face appeared so lifeless, frail, and colorless.

Introduction

Kumudini Lakhia’s development as a dancer is laid bare in Bridges. The author describes her lifelong pursuit of becoming a dancer in considerable detail, giving the work its “autobiographical” label.

The author opens with a discussion of the challenges inherent with dancing. She believes that dancing skill is learned and not innate.

Summary

The author has described her entire life in this essay. She describes the full story of how they had gone to the movies and how she enjoyed “Mumtaz Ali’s” dancing. When Kumudini’s mother observed her imitating the dance at home, she declared that the child was a great dancer and insisted she takes dance lessons

The author’s father was an engineer, and the family frequently moved about as a result of the British government’s support for India’s “independence battles and military activity.”

She also recalls a day when she and her brother burgled “Liaquat Ali’s” garden for fruit. Due to her father’s repeated relocations, she was enrolled in “Queen Mary’s College” in Lahore. Wher mother died just before her finals, she felt alone and abandoned.

She enrolled at “Allahabad’s agriculture college” later in life. Upon her graduation, she was accepted into London’s Ram Gopal Dancing School.

Her life shifted once she joined the dance troupe. Later she settled down, got married, and had children.

Kathak Dance

About the author

“Umrao Jaan” and “Sur Sangam”, two enduring films by “Kumudini Lakhia”, are well known.

Conclusion

The entire story demonstrates how, at her life’s most crucial turning points, bridges appeared, and it is because of these bridges her life entirely changed.

Textbook Question and Answers

1. How did the author feel about her mother’s passion to make her a dancer? 

Ans: The author struggled with her mother’s intense desire to turn her into a dancer. She claims that her mother realized she had an innate talent for dancing. This inspired the author’s mother to train her as a dancer. She claims that the film industry sparked her mother’s desire to train her as a dancer. The author explains her lack of interest in dancing as well as the difficulties she encountered getting to the dance teacher’s house. She had the impression that learning to dance had been forced upon her.

She first believed that she would not need to learn dance when she was sent to Queen Mary’s College in Lahore to pursue her studies. She finds it regrettable that her mother brought Radhelal Misra, a dance instructor, along with her. In this way, the author had a negative encounter with her mother’s desire to turn her into a dancer.

2. What were the lessons of life learned in her younger days that Kumudini carried into her adult life? 

Ans: When the author was younger, she encountered numerous lessons in life that she carried with her into adulthood. She recounts an incident that happened while she was living in a large mansion in Delhi that had been given to her father, They shared a border with Liaquat Ali, who eventually became Pakistan’s prime minister. She and her brother were once caught plucking guavas from his tree by his gardener. Liaquat Ali did not punish them; instead, he extended an open invitation for them to gather the fruits whenever they pleased. It was one of the first lessons in the games that politicians play, according to her.

Queen Mary’s College in Lahore provided her with the opportunity to understand the value of discipline. She believes that developing discipline in daily activities will result in discipline throughout her life. When her mother passed away, she learned about the hunger pangs, which are underlined in her work. The playwright was able to comprehend the type of tension she faced in David.

The author could develop the ability to tell the difference between sentimentality and sensitivity. In her adult years, she produced a work titled Panch Paras, five senses to investigate this area. She describes how Ram Gopal taught her that we should perfect the method before we start experimenting. Kumudini discovered more about herself while traveling with Ram Gopal.

3. How did Kumudini react to her mother’s death? 

Ans: The principal of the school where Kumudini was enrolled at the time did not directly inform her about her mother’s death. She was told to return home since her mother was ill. When she got home, she discovered her mother had died. She was just 14 years old at the time, her hands dangling loosely from her frame, and she felt powerless in the world. She was hungry but unable to communicate this to anyone. She was concerned that she’d come out as ungrateful.

4. What were the concepts that Kumudini Lakhia represented through Duvidha, Atah Kim, and Panch Paras? 

Ans: Kumudini examines the situation of a middle-class woman who is bound by Indian living norms in Duvidha or Conflict. The author of Atah Kim makes use of the idea of the need for power. In Panch Paras, the investigation of spiritual life is explained.

5. How does Kumudini Lakhia describe her guru Ramgopal’s influence on her? 

Ans: Kumudini Lakhia gave a detailed account of her guru Ramgopal’s impact on her. She claims that Ram Gopal was a harsh disciplinarian who had a passion for a precise line. This had an impact on the author, who attempted to teach her students the same lesson. She describes how going on a tour with Ram Gopal allowed her to learn more about herself.

 

Frequently Asked Questions

1. Why did the author start to dance?

Ans: The author didn’t start dancing until she was a little child. Her devoted mother and her silent, peace-loving father forced her to dance even though she didn’t want to.

2. Where did the author start taking dance classes?

Ans: The topic of the lesson is Bombay. His first dance training was given to the author by “Guru Sunder Prasad”. While the author was in “Khar”, he resided at “Chowpatty”. To get there, they had to take a train, a bus, and then a walk. It took 45 minutes each way for the full journey.

3. Why did the author’s mother sign her up for a dancing class?

Ans: Due to her admiration for the film industry, the author’s mother enrolled her in a dancing class. They took her to a movie when she was seven years old, and when they got home, she started dancing to the music and copying the performers.

4. My mother recognized this intrinsic talent in me. What kind of ability is the author referring to?

Ans: Her dancing ability is being discussed by the author. Although she insists she didn’t see it, her mother did. Her mother had such great faith in her that she enrolled her without hesitation in dancing classes four days a week.

Introduction

Electric charge is an intrinsic property of matter that allows it to experience a force when placed in an electric field. Charges are classified into two types or signs: positive, and negative. You can create a simple charged object by rubbing a balloon against your hair, which transfers charges from one body to another. This is what gives rise to static electricity, so named because there is no “flow” of charges here. You can do the same with carpets and other woollen items. In this article, we will discuss electric charges in detail.

Electric Charge Definition

Electric charge is a natural property of matter that allows it to experience a force when placed in an electric or magnetic field. It is a scalar quantity with no direction but it is classified into positive and negative types. 

Typically, charges are created via the transfer of electrons and the body that donates electrons is said to be positively charged, while the one that receives it becomes negatively charged. Just like magnets, like charges repel each other and opposite charges attract. Electrons are present in the atoms of every single element and thus, atoms are neutral as a whole, meaning that they carry no net charge. However, objects can gain charge via the transfer of electrons. Mathematically, the charge on an electron is equal to \(\;{\bf{1}}.{\bf{6}} \times {\bf{1}}{{\bf{0}}^{ – {\bf{19}}}}{\bf{C}}\). Further, charge is always transferred as an integral multiple of this quantity. That is, the charge on any object must be:

Q=ne

Q=total charge

e= charge on electron

n= number of electron

Basic properties of electric charge

Conservation of electric charge: Just like mass and energy always remain conserved in nature, electric charge is also a fundamental quantity that can never be created or destroyed. Rather, it is only transferred from body to body.

Example: Let us assume we have 15 C of charge on an object. We can redistribute it across several objects in any way we want, but we cannot make this charge vanish into nothingness.

Additive nature of electric charges: Since charges are scalar quantities, multiple charges on a system can be added algebraically.

For a system containing n number of charges \({q_1},{q_2},{q_3},…………{q_n}\), the total charge would be

\(Q = {q_1} + {q_2} + {q_3} + …………{q_n}\)

Note that if some of the charges are negative, that sign must be taken into account.

Quantization of electric charge: Since charge is always transferred as an integral multiple of the charge on one electron (represented by e), the total charge on any system is always quantized in units of e.

Q=ne

Transfer of charges: Charged bodies, when brought in contact, can exchange charges. That is, charge can flow across materials in contact in order for there to be equilibrium.

Like charges repel: Like charges repel each other. This fundamental property of charges is an essential force that keeps the universe stable and without it, nothing in this world would exist.

Like charges repel

Unlike charges attract: Just like magnets, unlike charges attract. This is what allows electrons to remain in orbit and thus, anything in this world to exist.

Linkage with mass: Charges cannot exist nowhere and must be present on some body.

Charge is invariant: Regardless of how fast a body moves and what frame of reference its speed is measured in, the charge on it remains the same.

Electromagnetic properties: Charges at rest produce an electric field and those in motion, produce a magnetic field. When charges are accelerated, they produce an electromagnetic field and give rise to electromagnetic radiation.

The Unit of Electric charge

The SI unit of the electric charge is coulomb, which is denoted by C, and in the CGS unit, it is measured in electrostat unit.

\(1C = \;3 \times {\bf{1}}{{\bf{0}}^{\bf{9}}}{\bf{C}}\)

Electric charge and field

When placed in an electric field, all electric charges experience a force, whose magnitude is given by the following relation:

F=qE

The sign of the charge and the direction of the electric field together decide the direction of this force. Note that E here represents the value of electric field and q is the charge placed inside it. For positive charges, the force is along the direction of the electric field and for negative ones, it is opposite. Note that this also allows us to define electric field as the force experienced per unit charge with SI units of N/C. That is,

\(E = \frac{F}{q}\)

Summary 

This article described the concept of electric charge along with its properties and units. Electric charge is an inherent property of matter that allows bodies to experience a force in the presence of a magnetic field. Charges themselves are attracted to unlike charges and repel like ones. This property of charge is what keeps the universe stable.

 

Frequently Asked Questions

1. How can we generate charged bodies?

We can generate charged bodies via friction, induction, or by conduction.

2. Write down the dimensional formula of the electric charge.

As such, charge has no inherent dimensions. Instead, the formula of current allows us to write its dimensions.

\(Q = I \times t\)

Thus, the dimensions of charge are \(\left[ {{M^0}{L^0}{T^1}{A^1}} \right]\).

3. Give examples of positive, negative, and neutral bodies.

Atoms yield the best example here. All electrons inside them are negatively charged, while the protons are positively charged. However, the neutrons carry no charge and thus are neutral.

4. Write down the practical unit of charges.

Practically, a common unit of charge used is Ampere hour.

1 Amp hr = 3600 C

5. Write the definition of electric field

The electric field is a property by virtue of which, a charged object can exert electric field on other charged objects in its vicinity. It is defined as the force per unit charge.

Introduction

In simple terms, force is just a way for two objects to interact. Its effect is that of a push or pull and it causes a change in the position and/or velocity of the object it is being applied on. The application of force also lends us the possibility of doing work as the object gets displaced.

Force is a vector quantity and thus, has both magnitude and direction. Therefore, for two forces to be truly equal, they must have the same magnitude and be applied in the same direction. When two forces of the same magnitude are applied on a body in opposite directions, they are said to be balanced. In such a case, the net force on the body is zero. An unbalanced force is encountered when the net force on the body isn’t zero.

What are Balanced Forces?

Balanced forces are those that act on a system with equal magnitude but in opposite directions. This results in a net force of zero on the system, causing it to remain in the state it was in (either at rest or in motion) with zero acceleration. In such a state, the body is said to be in equilibrium.

Example: Let’s consider four forces acting on the rectangular box the below diagram

Example of balanced forces.

The diagram attached below shows a rectangular box subject to four forces: 

• In the vertical direction, there is an upward force of 3 Newtons and a downward force of 3 Newtons. Since these forces are equal in magnitude but opposite in directions, they cancel each other out and result in no net force in the y-direction. 
• Similarly, the forces in the x-direction have equal magnitude but are in opposite directions, making them balanced as well. Thus, the rectangular box is experiencing balanced forces.

Examples of Balanced Forces

• Tug of war in which teams have equal members – The idea of tug of war is to pull the reference point on the rope beyond your line. However, if two identical teams were to play tug of war, they would exert identical forces on the rope, but in opposite directions. Thus, the rope would remain at rest and we have a state of balanced forces.
• Book on the table – A book when placed on a table is in equilibrium since its weight and the normal reaction due to the table cancel each other out.
• Person standing on the ground – When we stand still, we exert a force on the ground equal to our weight, and the ground exerts a normal reaction on us. Thus, we are in a state of equilibrium under balanced forces.

Characteristics of Balanced Force

• The state of rest or of motion of the body is not altered when it experiences balanced forces.
• A system under balanced forces is in static equilibrium.
• The net force on the system is zero when it is experiencing balanced forces.

Effect of a Balanced Force on a Body

When a body experiences balanced forces, the net or resultant force acting on the body is zero. This means that balanced forces do not cause any change in the state of the body. If the body is at rest, it will remain at rest under the balanced force, and if the body is in motion, it will continue to move at the same velocity.

What are Unbalanced Forces?

An unbalanced force is one that causes a change in the motion of a body. If the body is at rest, an unbalanced force can set it in motion and vice versa, if the body is already in motion, an unbalanced force can change its speed or direction. 

When two forces acting on a body have unequal magnitudes, the system is under unbalanced force. The resultant force on the body is not zero, resulting in non-zero acceleration and an absence of equilibrium condition.

Example: Suppose a book is placed on a table that has an incline. In that case, it will begin sliding down

A book placed on a table

In the vertical direction, the table experiences the vertical component of the book’s weight and applies a normal reaction on the book. These forces balance each other out, but in the horizontal direction, the frictional force cannot balance the horizontal component of the book’s weight and thus, the book begins to slide down.

Examples of Unbalanced Forces

• Tug of war in which teams have unequal members – For a tug of war game where the two teams aren’t identical, one of them will apply a larger amount of force and end up winning the same.
• See saw the game – Since the two people sitting on the see-saw don’t have identical weights, this is an example of unbalanced force. 
• Kicking a ball – A ball receiving a kick receives an unbalanced force.

Difference between Balanced and Unbalanced Forces

Summary

This article explains the concept of forces and their two main types: balanced and unbalanced forces. Balanced forces do not affect the state of an object, whereas unbalanced forces are responsible for its motion. 

A body under the effect of balanced forces experiences no net acceleration or force, but unbalanced forces can cause net acceleration in the system. Another major difference is that balanced forces can only alter the geometry (shape or size) of the object, whereas unbalanced forces can also alter its state of motion.

Frequently Asked Questions

1. What are the possible states of motion?

The two states of motion are as follows:

1. A body can remain at rest, which is when it has no motion with respect to a reference point.
2. The second state is that of motion wherein, the body is moving with a certain velocity.

2. Can a balanced force deform a body?

Yes. While movement isn’t possible due to balanced forces, the geometry of the object can get altered.

3. Given acceleration, how do we find force?

According to Newton’s second law, force is equal to mass times the acceleration. That is,

F=ma

4. What unit is force measured in?

The S.I. unit of the force is newton or \({kgms^{-2}}\). In C.G.S. system, it is dyne or \({gcms^{-2}}\).

5. Give one daily life example of balanced force.

Screws or clips experience frictional force from the wall. This allows us to hang items on the walls which experience balanced forces and thus, do not fall down.

Introduction

The concept of pressure plays an integral role in our daily activities. For instance, a knife edge exerts a large amount of pressure on fruits and vegetables. While the science behind it may be new for some people, this occurs because the edge of the knife is very sharp. Surfaces that have small areas exert larger amounts of pressure and it is this property that enables us to cut fruits and vegetables using knives.

It is also pressure that allows various other devices like pumps and vacuum cleaners to function.

What is Pressure?

Pressure is the term used to describe the force applied on an object per unit area of the surface in a perpendicular direction and thus, it can be expressed as the ratio of force to area. Most commonly, we use the symbol ‘p’ to denote pressure and measure in the Sl unit of Pascal (Pa). In CGS systems, its unit is barye (Ba). Note that it is a scalar quantity with only magnitude and no direction.

For liquids, we define a quantity known as thrust. It is the total force acting on the surface of a solid that is touching the liquid. Thus, it has the same units as force and the formula also doesn’t differ:

\[thrust = pressure \times area\]

Hence, for liquids, we can also find pressure as thrust per unit area.

Pascal’s law states that pressure in a liquid is transmitted equally in all directions and thus, pressure at any point is unaffected by the shape of the vessel. The pressure exerted by the liquid at any given point is uniform and the force exerted by a liquid at rest is always normal to the surface in contact with it. 

Mathematically, the pressure at any point within the liquid is directly proportional to its density as well as the height of the liquid column above it. Hence, we can relate pressure at any point in a liquid column to these two quantities via the relation

\[{\bf{p}} = {\bf{h}}\rho {\bf{g}}\]

Here, is the density of the liquid, h is the height above it, and g is acceleration due to gravity.

Types of Pressures

1. Absolute Pressure:

Absolute pressure is the measurement of pressure in vacuum or empty space. It is measured from the absolute zero or absence of pressure and may be given as the combination of atmospheric and gauge pressure.

Absolute pressure = Atmospheric pressure + Gauge pressure

As an example, if we have

 Gauge pressure = 14 psi

 Atmospheric pressure = 30.5 psi

Absolute pressure = 14+ 30.5=44.5 psi

2. Gauge Pressure:

Gauge pressure refers to the pressure that is measured above the atmospheric pressure. When the atmospheric pressure is low, the gauge pressure will have a positive value, and vice versa. We can measure gauge pressure via the use of instruments known as manometres and gauges.

 Gauge pressure = Absolute pressure – Atmospheric pressure

3. Differential Pressure:

As implied by the name, differential pressure is a measure of the pressure difference that exists between two points. If \({P_{a}}\) and \({P_{b}}\) are pressures at two points a and b, then the differential pressure is given as

Venturi tube is a device that can best demonstrate the concept of differential pressure. It is used to measure the flow of fluids and can change the pressure in the middle, making it best suited to measure liquid pressure.

4. Sealed Pressure or Vacuum Pressure:

Vacuum is defined as a portion of space wherein there exists no matter and thus, it has zero pressure. Practically, such a condition is hard to achieve but a close enough situation may be arrived at by using sealed containers made of very strong materials.

What is Gauge Pressure?

Pressure measured over the atmospheric pressure is known as gauge pressure and it can be calculated as follows:

Local atmospheric pressure = 14.2psi

Absolute pressure = 28 psi

 Gauge pressure = Absolute pressure – Atmospheric pressure   

Gauge pressure= 28-14.2=13.8psi

Sometimes, we also refer to it as overpressure. It gives us an idea about the atmospheric weight of a point and is different under different weather conditions and sea level.

Relation Between Atmospheric Pressure and Gauge Pressure:

Pressure exerted by the atmosphere at any point is referred to as atmospheric pressure. The atmosphere is composed of a mixture of various gases and these gases exert a pressure due to the weight of the molecules above it. 

We can relate gauge pressure and atmospheric pressure via the absolute pressure

Gauge pressure = Absolute pressure – Atmospheric pressure  

Since absolute pressure is fixed, gauge pressure must become negative if the atmospheric pressure exceeds a certain threshold and vice versa.

Difference between Absolute and Gauge Pressure

Summary

Pressure is something fundamental that we experience in our everyday activities but often fail to notice. From cutting fruits with a knife-edge to breaking stones using chisels, our actions involve some level of pressure in one way or another. The amount of pressure required to do some task depends on where and how the force or thrust is applied as well as the area it is applied on. Mathematically, pressure is given as the ratio of force and area and thus, is higher for smaller areas.

Frequently Asked Questions

1. Explain the Bourdon Gauge instrument?   

This instrument can directly measure gauge pressure and thus, is utilised extensively in industrial settings to measure both small and large pressures.

2. What are Barometers?

The instruments used to measure atmospheric pressure are known as barometres. The most common and widely used type of barometer is the cistern-type Fortin’s Barometer. Another handy type is the aneroid barometer which does not use any liquid inside it.

3. A bike tire measures a gauge pressure of 35 psi. Find the Absolute Pressure.

Given that,

4. Football shoes have studs on them. Does the concept of pressure play a role here?

Studs have smaller surface areas and thus, exert higher pressure, allowing them to sink into the ground and provide a better grip.

5. What is Atmospheric Pressure?

Ans: Pressure exerted by the atmosphere is known as atmospheric pressure and it is present everywhere on Earth. Its value decreases as we go higher up.