# Induced EMF and Lenz’s law

##### Intros
###### Lessons
1. Induced emf
2. The relative motion between the magnet and coil induces current (Lenz's law).
##### Examples
###### Lessons
1. A bar magnet is moving toward a solenoid.

What is the direction of the current through the galvanometer and what is the the direction of the magnetic field produced by thus current at location P inside the solenoid?

1. A magnet is moving toward an aluminum ring.

In which way will the current flow in the labelled portion of the ring as the magnet moves towards the ring?

1. Towards 1
2. Towards 2
3. Towards 3
4. Towards 4
1. A coil moves at a constant velocity across a region of magnetic field as shown.

Which of the following best shows the emf vs. time graph for the emf induced in the coil as it moves from 1 to 2?

1. A conductor is moved to the right through four magnetic field as shown below. In which case will the largest emf be generated?
1. A bar magnet is moved away from a coil as shown. What is the direction of the current through the resistor and polarity of the left end of the coil?
1. In which of the following situation would the greatest emf be induced in the coil? All changes occur in the same time interval.