AP Physics 2

Which of the following are situations where a magnet can induce a current in a coil of wire?

• If you move a magnet in and out of the coil

• If you move the coil in and out of a magnet

• If you put multiple magnets near the coil

• If you open or close the circuit with the coil

Answer explanation

Induced currents arise when there is a changing magnetic field

Tags

NGSS.HS-PS2-5

What does the motional emf of a conductor depend on?

• strength of magnetic field

• speed of conductor

• length of conductior

• resistance of the wire

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

Which of the following does NOT cause changing flux in a loop?

• The loop changing area or angle

• The loop has a charge

• The magnetic field through the loop changes

• The loop moves in or out of the magnetic field

Answer explanation

This is what Lenz's Law tells us: an induced current opposes the change in flux. Flux is area x magnetic field x angle, changing any of those will change the flux

How do we represent vectors going into the page?

Answer explanation

Hopefully, you drew an x! Imagine an arrow: if it's going into the page, we can see the back end of the arrow.

What are some examples of "at-a-distance" forces? (Give 3. Hint: which forces involve fields?)

Answer explanation

Magnetic, electric, and gravitational forces are "at-a-distance" forces; no contact necessary.

Tags

NGSS.HS-PS2-4

NGSS.HS-PS3-5

True or false: every magnet is a dipole.

• True

• False

Answer explanation

A magnet will always have a north pole and a south pole; 2 poles = dipole.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

Which fields can be monopole fields?

• Electric

• Magnetic

• Gravitational

Answer explanation

Gravitational fields and electric fields can be monopole, while magnetic fields are always dipole.

Tags

NGSS.HS-PS2-4

Draw the magnetic field around a bar magnet. (Be sure to include the magnet!)

Tags

NGSS.HS-PS3-5

What is the magnetic field of a current-carrying wire?

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NGSS.HS-PS2-5

NGSS.HS-PS3-5

What is the magnetic field at the center of a single loop?

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NGSS.HS-PS2-5

NGSS.HS-PS3-5