Magnetism

If the North Pole of a permanent magnet is placed next to a compass as seen in the picture, which direction will the needle move?

• Clockwise
• Counter-clockwise
• It will not move
• Need more information

Electric motors are devices that convert _____ energy into  _____ energy.

• electrical; mechanical
• mechanical; electrical
• chemical; potential
• mechanical; kinetic

The strongest part of a magnet is...

• the bars.
• the force field.
• the poles. 
• the middle.

What causes magnetism?

• the sun

• moving neutrons

• moving charges

• friction

What is an electromagnet?

• a magnet that creates an electric current
• a magnet created by an electric current
• a magnet that has an electric charge
• an electric charge that is magnetic

2 ways to increase the magnetic force of an electro-magnet

• Increase the current flow, reduce the number of coils
• Increase the voltage, decrease the number of coils
• Increase the number of coils and the current flow
• Spread out the coils, replace iron core with rubber.

Generators are devices that convert ______ energy into ______ energy.

• chemical; mechanical
• mechanical; electrical
• electrical; mechanical
• potential; kinetic

If positive x-axis is symbolized as current flow and positive z-axis is symbolized as magnetic field direction. then the direction of the Lorentz force is symbolized as ....

• positive x-axis

• negative y-axis

• positive y-axis

• negative z-axis

A 2.0 m long wire carrying 10 A of current moves through an 6.0 T magnetic field. What is the magnetic force acting on the wire?

• 10 N

• 120 N

• 0.5 N

• 2 N

Two long parallel wires carry currents in opposite directions. The top wire carries a current to the left, while the bottom wire carries a current to the right. The wires are not touching. Do the wires attract each other or repel?

• Attract

• Repel