A magnet swings toward a coil. Is an EMF induced while it swings?
The same magnet enters the same coil twice, once slowly and once fast. During the slow push, the meter reads 0.2 V. During the fast push, it reads 0.6 V.
The only difference between the two pushes is speed. The fast push changes the field through the coil more quickly.
The rule covers every kind of change: moving a magnet faster, sweeping a wire faster, or switching a neighboring coil's current more quickly.
A slower change works the other way: it induces a smaller EMF.
A magnet is pulled out of a coil quickly. An identical pull is then made slowly. Which pull induces the larger EMF?
The quick pull changes the field through the coil more quickly.
A faster change induces a larger EMF.
The quick pull induces the larger EMF.
The current in an electromagnet is made to fall slowly instead of quickly. What happens to the size of the EMF induced in a loop beside it?
A slower fall in the current changes the field through the loop more slowly.
A slower change induces a smaller EMF.
The induced EMF is smaller.
The same magnet enters the same coil, faster than before. What happens to the size of the induced EMF?
The magnet is withdrawn more slowly than before. What happens to the size of the induced EMF?
A dimmer raises a coil's current more quickly than before. What happens to the size of the EMF induced in a coil beside it?
A magnet swings in and out of a coil, and the swinging slowly dies down. What happens to the size of the induced EMF as the swinging dies down?
A magnet is dropped through a coil twice: once from just above it, and once from high above it, so it arrives moving faster. Which drop induces the larger EMF at the coil?
Which change makes the EMF induced in a coil larger, with everything else unchanged?