12.3-Types of Charges and Their Interaction

12.3-Types of Charges and Their Interaction Important Formulae

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12.3 - Types of Charges and Their Interaction
  • There are two types of charges: Positive (+) and Negative (–).
  • Like charges repel each other, while opposite charges attract each other.
  • When two objects are rubbed together, electrons are transferred, leading to the development of charges.
  • Electrostatic force: The force between two charged objects is given by $F = k \frac{q_1 q_2}{r^2}$, where $q_1$ and $q_2$ are charges, $r$ is the distance between them, and $k$ is Coulomb's constant.
  • Charges can be transferred by conduction, induction, or friction.

12.3-Types of Charges and Their Interaction

In this section, we will learn about the two types of electric charges and how they interact with each other. Electric charges are the fundamental property of matter responsible for electrical phenomena. There are two types of charges:

  • Positive charge
  • Negative charge

Electric charge is a scalar quantity and can be either positive or negative. Like charges repel each other, whereas opposite charges attract each other.

Types of Electric Charges

Electric charges come in two forms:

  1. Positive Charge: A charge that has more protons than electrons. The proton is the particle that carries a positive charge. A body with more protons than electrons becomes positively charged.
  2. Negative Charge: A charge that has more electrons than protons. Electrons carry a negative charge. A body with more electrons than protons becomes negatively charged.
Interaction of Charges

The interaction between two charges depends on whether they are of the same type or different types. The key principles are:

  • Like charges repel each other: If two objects have charges of the same type (both positive or both negative), they will push away from each other. This is called repulsion.
  • Opposite charges attract each other: If one object has a positive charge and the other has a negative charge, they will attract each other. This is called attraction.
Force Between Charges (Coulomb's Law)

The force between two electric charges can be calculated using Coulomb’s law. Coulomb’s law states that:

The force between two point charges is directly proportional to the product of the magnitudes of the charges and inversely proportional to the square of the distance between them.

The formula for Coulomb's law is given by:

$F = k \cdot \frac{q_1 q_2}{r^2}$

Where:

  • $F$ is the force between the charges (in newtons, N).
  • $q_1$ and $q_2$ are the magnitudes of the two charges (in coulombs, C).
  • $r$ is the distance between the charges (in meters, m).
  • $k$ is Coulomb’s constant, which is approximately $8.99 \times 10^9 \, \text{N·m}^2/\text{C}^2$.
Conductors and Insulators

Electric charges can be transferred between bodies, but the way charges move depends on the material of the body:

  • Conductors: Materials that allow electric charges to move freely. Examples include metals like copper, silver, and aluminum.
  • Insulators: Materials that do not allow electric charges to move freely. Examples include rubber, plastic, and glass.

In conductors, electrons are free to move, so electric charge can flow easily. In insulators, electrons are tightly bound to atoms, preventing the movement of charges.

Charging by Induction

Charging by induction is the process by which a charged object can induce a charge in a neutral object without direct contact. For example, if a negatively charged rod is brought near a neutral conductor, the electrons in the conductor will rearrange themselves. This process does not require physical contact with the charged object.

In induction, one side of the neutral object becomes oppositely charged (attracted to the charged object), while the other side becomes similarly charged (repelled). If the neutral object is grounded, it will acquire a charge of the opposite type.

12.3-Types of Charges and Their Interaction

चार्ज (आवेश) एक भौतिक गुण है जो पदार्थ के कणों को प्रभावित करता है। आवेश मुख्य रूप से दो प्रकार के होते हैं:

1. धनात्मक चार्ज (Positive Charge)

धनात्मक चार्ज उन कणों में होता है जिनमें इलेक्ट्रॉनों की तुलना में प्रोटॉनों की संख्या अधिक होती है। उदाहरण: कांच की छड़ जब रेशम के कपड़े से रगड़ी जाती है तो उसमें धनात्मक चार्ज उत्पन्न होता है।

2. ऋणात्मक चार्ज (Negative Charge)

ऋणात्मक चार्ज उन कणों में होता है जिनमें प्रोटॉनों की तुलना में इलेक्ट्रॉनों की संख्या अधिक होती है। उदाहरण: एबोनाइट की छड़ जब ऊन के कपड़े से रगड़ी जाती है तो उसमें ऋणात्मक चार्ज उत्पन्न होता है।

चार्ज के गुण

आवेश के मुख्य गुण निम्नलिखित हैं:

  • आवेश के दो प्रकार होते हैं: धनात्मक और ऋणात्मक।
  • एक ही प्रकार के आवेश (जैसे धनात्मक-धनात्मक या ऋणात्मक-ऋणात्मक) एक-दूसरे को प्रतिकर्षित करते हैं।
  • विभिन्न प्रकार के आवेश (जैसे धनात्मक-ऋणात्मक) एक-दूसरे को आकर्षित करते हैं।
चार्ज के परस्पर क्रिया

जब दो आवेशित वस्तुएं पास में लाई जाती हैं, तो वे एक-दूसरे पर बल लगाती हैं। इस बल की प्रकृति निम्नलिखित हो सकती है:

  1. आकर्षण (Attraction): यदि वस्तुएं भिन्न प्रकार के चार्ज (धनात्मक और ऋणात्मक) रखती हैं, तो वे एक-दूसरे को आकर्षित करती हैं।
  2. प्रतिकर्षण (Repulsion): यदि वस्तुएं समान प्रकार के चार्ज (धनात्मक-धनात्मक या ऋणात्मक-ऋणात्मक) रखती हैं, तो वे एक-दूसरे को प्रतिकर्षित करती हैं।
कूलॉम्ब का नियम (Coulomb's Law)

कूलॉम्ब का नियम दो आवेशित कणों के बीच बल की गणना के लिए उपयोग किया जाता है। यह कहता है:

$F = k \cdot \frac{q_1 \cdot q_2}{r^2}$

जहां:

  • $F$: बल (न्यूटन में)
  • $q_1$ और $q_2$: दो आवेशों का परिमाण
  • $r$: दोनों आवेशों के बीच की दूरी (मीटर में)
  • $k$: कूलॉम्ब का स्थिरांक, जिसका मान $8.99 \times 10^9 \, \text{Nm}^2/\text{C}^2$ है।
उदाहरण

यदि एक कांच की छड़ को रेशम के कपड़े से रगड़ा जाए, तो:

  • कांच की छड़ धनात्मक चार्ज प्राप्त करती है।
  • रेशम का कपड़ा ऋणात्मक चार्ज प्राप्त करता है।

जब दोनों को पास लाया जाता है, तो वे एक-दूसरे को आकर्षित करते हैं।