Topic 7: Physics AQA

Which electromagnet is stronger?

• A

• B

Use F=BIL to solve this problem: A wire 0.10 m long carries a current of 5.0 A. The wire is at right angles to a uniform magnetic field. The force the field exerts on the wire is 0.20 N. What is the magnitude of the magnetic field?

• 4.0

• 0.04

• 0.4

• 40

What is the direction of the force?

• into the page

• left

• out of the page

• right

How could the experimenter increase the amount of electricity being induced by this experiment?

• Increase the number of coils
• Decrease the number of coils
• Flip the magnet around
• Nothing, the amount of electricity cannot be increased

How would flipping the magnet in this experiment change the current?

• The current would not change
• The current would go to the right
• There would be no current
• The current would go CRAZY

Electromagnetic induction is change in ___________________. 

• surface area
• magnetic poles
• magnetic flux

Voltage can be induced in a wire by

• a. moving the wire near a magnet.
• b. moving a magnet near the wire.
• c. changing the current in a nearby wire.
• d. all of these

What would happen if I move a bar magnet in and out of a coil of copper wire?

• Electric current would disappear 
• The magnet would explode 
• Electric current will flow through the wire
• It would produce a gravitational field

When a conductor is moved to cut through the magnetic flux, an _______________ is produced.

• induced current

• electromotive force

• electromagnetic induction

• internal resistance

Electromagnetic induction occurs in a coil when there is a change in

• electric field in the coil

• magnetic field in the coil

• voltage in the coil