Faraday’s Law of Induction - Induced emf - Magnetic force and energy loss due to induced current

Slide 1:

  • Introduction to Faraday’s Law of Induction
  • Definition of induced emf
  • Importance and applications of Faraday’s Law

Slide 2:

  • Description of a basic setup for demonstrating Faraday’s Law
  • Consists of a coil of wire, a magnet, and a galvanometer
  • Explanation of how the induced emf is generated

Slide 3:

  • Formula for calculating induced emf:
    • emf = -N dΦ/dt
    • The negative sign represents the direction of the induced current

Slide 4:

  • Explanation of the variables in the formula:
    • emf is the induced electromotive force
    • N is the number of turns in the coil
    • dΦ/dt is the rate of change of magnetic flux

Slide 5:

  • Example calculation of induced emf:
    • Given: N = 100 turns, dΦ/dt = 0.05 T/s
    • Calculation: emf = -100 * 0.05 = -5 V
    • Interpretation of the negative sign

Slide 6:

  • Magnetic force exerted on a current-carrying conductor in a magnetic field
  • Formula for magnetic force:
    • F = BIL sinθ
    • Explanation of the variables in the formula

Slide 7:

  • Description of the force direction using Fleming’s left-hand rule
  • Application of the rule to determine the direction of the force on a current-carrying conductor

Slide 8:

  • Calculation of magnetic force on a wire:
    • Given: B = 0.1 T, I = 2 A, L = 0.5 m, θ = 30 degrees
    • Calculation: F = 0.1 * 2 * 0.5 * sin(30) = 0.05 N
    • Interpretation of the magnitude and direction of the force

Slide 9:

  • Energy loss due to induced current
  • Explanation of how energy is dissipated in the form of heat
  • Relation between power and resistance: P = I^2R

Slide 10:

  • Calculation of energy loss:
    • Given: I = 5 A, R = 10 Ω, t = 60 s
    • Calculation: P = (5)^2 * 10 = 250 W
    • Energy loss: Q = Pt = 250 * 60 = 15000 J
    • Interpretation of the energy loss and its significance.

Slide 11:

  • Introduction to Lenz’s Law
  • Explanation of how Lenz’s Law relates to Faraday’s Law of Induction
  • Statement of Lenz’s Law: The direction of an induced current is such that it opposes the change that produced it

Slide 12:

  • Example of Lenz’s Law:
    • Description of a coil and a magnet approaching each other
    • Explanation of how the induced current creates a magnetic field that opposes the motion

Slide 13:

  • Self-induction and inductance
  • Definition of self-inductance: The property of a circuit that opposes any change in the current flowing through it

Slide 14:

  • Formula for calculating self-inductance:
    • L = Φ/I
    • Explanation of the variables in the formula

Slide 15:

  • Example calculation of self-inductance:
    • Given: Φ = 2 Wb, I = 1 A
    • Calculation: L = 2 / 1 = 2 H
    • Interpretation of the unit Henry (H)

Slide 16:

  • Mutual induction and mutual inductance
  • Definition of mutual induction: The process by which a changing magnetic field in one coil induces an emf in a neighboring coil

Slide 17:

  • Formula for calculating mutual inductance:
    • M = Φ2 / I1
    • Explanation of the variables in the formula

Slide 18:

  • Example calculation of mutual inductance:
    • Given: Φ2 = 3 Wb, I1 = 2 A
    • Calculation: M = 3 / 2 = 1.5 H
    • Interpretation of mutual inductance and its relation to self-inductance

Slide 19:

  • Induced emf in a solenoid
  • Explanation of how the induced emf in a solenoid is related to the rate of change of current and the number of turns

Slide 20:

  • Formula for calculating induced emf in a solenoid:
    • emf = -N dI/dt
    • Explanation of the variables in the formula, including the negative sign indicating the direction of the induced current

Slide 21:

  • Introduction to electromagnetic induction
  • Explanation of how a changing magnetic field can induce an emf in a conductor

Slide 22:

  • Explanation of Faraday’s Law of electromagnetic induction
  • Statement: The magnitude of the induced emf in a circuit is directly proportional to the rate of change of magnetic flux through the circuit

Slide 23:

  • Factors affecting the magnitude of induced emf:
    • Number of turns in the coil
    • Rate of change of magnetic flux
    • Angle between the magnetic field and the coil

Slide 24:

  • Example of induced emf in a rotating coil:
    • Description of a generator consisting of a rotating coil and a magnet
    • Explanation of how the changing magnetic field induces an emf in the coil

Slide 25:

  • Applications of electromagnetic induction:
    • Generators for electricity production
    • Induction motors for various mechanical applications
    • Transformers for voltage regulation

Slide 26:

  • Introduction to self-inductance and inductors
  • Definition of self-inductance: The ability of a circuit to oppose any change in the current flowing through it

Slide 27:

  • Explanation of how self-inductance is represented by an inductor
  • Symbol and construction of an inductor
  • Inductance as a measure of the inductor’s self-inductance

Slide 28:

  • Calculation of induced emf in an inductor:
    • Explanation of the formula emf = -L dI/dt
    • Example calculation with a changing current and inductance value

Slide 29:

  • Introduction to mutual inductance
  • Definition: The property of two coils to induce an emf in each other when the current in one coil changes

Slide 30:

  • Explanation of mutual inductance between two coils
  • Explanation of the formula emf = -M dI/dt
  • Examples of applications of mutual inductance in transformers and wireless charging systems