Lesson Check: Electromagnetism

Which statement is true?

• As the electric current through a wire increases, the magnetic field around the wire becomes stronger.

• As the electric current through a wire increases, the magnetic field around the wire becomes weaker.

• As the electric current through a wire increases, the magnetic field around the wire is unaffected.

• As the electric current through a wire decreases, the magnetic field around the wire becomes stronger.

Tags

NGSS.MS-PS2-3

Which of the following conditions is necessary for a magnet inside a wire loop to produce an electric current?

• The magnet must be stationary.

• The wire loop must be part of an open circuit.

• The wire loop must already have a current running through it.

• The magnet must be in motion.

Tags

NGSS.HS-PS2-5

Which statement is false?

• The direction a magnet moves through a coil of wire determines the direction of the electric current.

• The direction a coil of wire moves through a magnetic field determines the direction of the electric current.

• Current will flow through a wire as long as the magnetic field around the coil is changing.

• Current will not flow though a wire if the magnet is outside the coil.

Tags

NGSS.HS-PS2-5

By changing the current in the wire, you can change the _____ of an electromagnet.

• strength and charge

• direction and coils

• charge and strength

• strength and direction

Changing _________________ of the current in a wire coils reverses an electromagnet’s north and south poles.

• direction

• length

• temperature

• thickness

Which is the best prediction for what will happen to the reading on the meter when the magnet stops and then is moved down through the loop of wire?

• The reading will not change.

• The reading will drop to zero and then return to the same reading.

• The reading will drop to zero and then move in the negative direction.

• The reading will drop to zero and remain there.

Tags

NGSS.MS-PS2-3

In the figure shown, what happens when the amount of current flowing in the wire coil is increased?

• The magnetic field becomes stronger.

• The magnetic field disappears.

• The position of the north and south poles is reversed.

• The strength of the magnetic field decreases.

Tags

NGSS.MS-PS2-3

In the figure shown, what would happen if the direction of the current in the wire coil were reversed?

• The electromagnet would no longer work.

• The north and south poles would switch places.

• The strength of the magnetic field would increase.

• The strength of the magnetic field would decrease.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

An electromagnet is a current-carrying wire wrapped around a copper core.

• True

• False

Which of the following lists three ways to increase the strength of an electromagnet?

• Increase the number of coils, increase the current, use a core with higher magnetic permeability.

• Decrease the number of coils, use a plastic core, reduce the current.

• Use a thinner wire, decrease the voltage, use a wooden core.

• Reduce the current, use fewer coils, use a non-magnetic core.