Unit 11 Test: Electricity and Magnetism

The force or push that causes electric charges to move is called

• resistance
• voltage difference
• current
• static electricity

Electric charges always flow from _______ areas to ______areas.

• positive, negative
• positive, netural
• negative, positive
• neutral, negative

A material through which electrons do NOT flow easily is a(n)

• insulator
• conductor
• fuse
• circuit breaker

Which of the following statements about electric charge is true? (Choose electrical forces act at a distance)

• Objects must be touching one another to exert electrical force.
• Electrical forces act at a distance
• Air cannot conduct electricity; it is conducted only by solid materials
• Opposite electric charges always repel one another.

Mr. Smith and his lass are conducting an experiment. The class needs to choose a good insulator. Which of the following could be used as an insulator?

• plastic plate
• silver spoon
• copper wire
• gold necklace

Which of the following will increase the resistance of a wire?

• using a thicker/wider wire
• using a shorter wire
• increasing the temperature of the wire
• using silver instead of copper

What is the current produced by a 9-volt battery flowing through a resistance of 0.2 ohms?

• 1.8 amps
• 45 amps
• 0.022 amps
• 8.8 amps

Which two areas of physical science are closely related to the development of electric motors and generators?

• sound and light
• electricity and sound
• light and magnetism
• electricity and magnetism

Which of the following will decrease the strength of the magnetic field around a wire? (Choose using less loops)

• increasing the current flowing through the wire
• using less loops around the iron core
• flipping the direction of the current flowing through the wire
• using a larger iron core

Silver has a resistance of 0.0198 ohms. What voltage would produce a current of 100 amps?

• 0.000198 V
• 5,050 V
• 100.0198 V
• 1.98 V