Diagram below shows the apparatus used to study the effect of an electromagnet.

Which change will increase the number of paper clips attracted to the iron rod?

• Use a thinner wire to form the coils

• Use a non-insulated wire to form the coils

• Reduce the number of coils

• Increase the magnitude of the current

Diagram below shows a simple transformer.

The bulb lights up at normal brightness.

What happens if the a.c. input is replaced by a 3 V battery?

• The bulb does not light up

• The brightness of the bulb remains unchanged

• The brightness of the bulb increases

• The bulb blows

Particles with opposite charges ____________ and particles with same (or like) charges ____________.

• attract, repel

• repel, repel

• attract, attract

• repel, attract

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

Where is the force of attraction the strongest on a magnet?

• at the poles
• in the middle
• above the magnet
• below the magnet

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

Which device uses mechanical energy to produce electrical energy?

• Electric Motor
• Magnet
• Generator
• Solar Cell

Tags

NGSS.HS-PS3-3

A device that increases or decreases the voltage of alternating current

• A. magnet
• B. magnetic pole
• C. transformer
• D. magnetic force

Which side of this picture would be a north pole?

• A

• B

Which of the following will most affect the strength of a magnetic field inside a solenoid?

• the diameter

• the number of coils

• the current

• the number of coils & the amount of current

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

• Lenz'
• Faraday's
• Ampere's

Tags

NGSS.HS-PS2-5

___ Law says that a current produced by an induced emf moves in a direction so that its magnetic field opposes the original change in flux

• Lenz'
• Faraday's
• Ampere's

Tags

NGSS.HS-PS2-5