Magnetic induction

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

A magnet is moved in and out of a coil of wire connected to a high-resistance voltmeter. If the number of coils doubles, the induced voltage 

• quadruples
• doubles
• is the same
• halves

A magnet can move in a coil of wire to produce electricity in which system?

• Generator
• Motor
• Magnet
• Transformer

___ Law says that the Induced current is proportional to the change of magnetic flux 

• Lenz'
• Faraday's
• Ampere's

Which activity will produce the highest current?

• Move the magnet bar into the coil while the coil remains stationery

• Move the coil into the magnet bar while the magnet remains stationery

• Move the coil and magnet towards each other

• Move the coil and magnet away from each other

Which action will increase the deflection of the galvanometer pointer?

• The magnetic pole is reversed

• The number of turns of coils is increased

• The coil is made from insulated wire

• The magnet is slowly pushed into the coil

What is one way to increase the current in a wire?

• Decrease the number of coils
• Increase the number of coils
• Move the magnet slower
• Take the wire off of the magnet

What benefit is gained by the addition of the iron core in an electromagnet?

• It makes a strong magnet weaker
• It makes a weak magnet stronger
• There is no benefit at all
• It lets currents interact with each other