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Physics Chapter 29: Electromagnetic Induction and Related Concepts

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  • What is the letter and SI unit for magnetic flux?
    Magnetic flux is represented by \(\Phi_B\) and measured in tesla square meters (T·m²), also called webers (Wb).
  • What is the letter and SI unit for displacement current?
    Displacement current is represented by \(i_D\) and measured in amperes (A).
  • What is the letter and SI unit for induced emf?
    Induced emf is represented by a cursive E (ℰ) and measured in volts (V).
  • What is the letter and SI unit for velocity?
    Velocity is represented by \(v\) and measured in meters per second (m/s).
  • What is the letter and SI unit for angular frequency?
    Angular frequency is represented by \(\omega\) and measured in radians per second (rad/s).
  • State Lenz's rule in terms of induced emf and magnetic flux change.
    A change of magnetic flux through a wire loop induces an emf whose direction produces a magnetic field opposing the change in flux.
  • According to Lenz's rule, what is the direction of the induced magnetic field if magnetic flux increases?
    The induced magnetic field is opposite to the external magnetic field.
  • According to Lenz's rule, what is the direction of the induced magnetic field if magnetic flux decreases?
    The induced magnetic field is in the same direction as the external magnetic field.
  • Write Faraday's law of induction (both parts).
    Induced emf: \(\mathcal{E}_{ind} = -N \frac{d\Phi_B}{dt}\), where magnetic flux \(\Phi_B = B A \cos \theta\).
  • Write the generator equation for induced emf.
    Induced emf: \(\mathcal{E}_{ind} = N B A \omega \sin(\omega t)\).
  • Write the motional emf equation.
    Induced emf: \(\mathcal{E}_{ind} = v B L\).
  • What produces electric fields according to the 'constant thing' equation?
    Charges produce electric fields: \(\oint E \cdot dA = \frac{Q_{encl}}{\epsilon_0}\).
  • What produces magnetic fields according to the 'constant thing' equation?
    Currents produce magnetic fields: \(\oint B \cdot dl = \mu_0 i_{encl}\).
  • What produces electric fields according to the 'changing thing' equation?
    A changing magnetic field produces electric fields: \(\oint E \cdot dl = -\frac{d\Phi_B}{dt}\).
  • What produces magnetic fields according to the 'changing thing' equation?
    A changing electric field produces magnetic fields: \(\oint B \cdot dl = \mu_0 \epsilon_0 \frac{d\Phi_E}{dt}\).