AP Physics 2 Magnetism Review

Which of the following is true about field lines? (Select all that apply)

• They go from a north magnetic pole to a south magnetic pole

• They go from a south magnetic pole to a north magnetic pole

• Their spacing shows the strength of the field

• They cannot cross

Answer explanation

Just like for electric fields, magnetic field lines allow us to represent the features of a magnetic field. Their spacing and direction indicate the strength and direction of the field and they start at the north magnetic pole and end at the south magnetic pole (never crossing!).

Tags

NGSS.HS-PS3-5

How does a magnetic field affect a moving electric charge?

• It doesn't

• It exerts a force parallel to the velocity of the charge and parallel to the direction of the field

• It exerts a force perpendicular to the velocity of the charge and parallel to the direction of the field

• It exerts a force perpendicular to the velocity and perpendicular to the direction of the field

Answer explanation

Remember your right hand rule! The velocity the charge, the direction of the field, and the force the charge experiences are all perpendicular to each other.

How does a magnetic field affect a stationary electric charge?

• It doesn't

• It exerts a force parallel to the velocity of the charge and parallel to the direction of the field

• It exerts a force perpendicular to the velocity of the charge and parallel to the direction of the field

• It exerts a force perpendicular to the velocity and perpendicular to the direction of the field

Answer explanation

A magnetic fields only exert a force on a moving electric charge.

Tags

NGSS.HS-PS3-5

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.

How do we represent vectors going out of the page?

Answer explanation

Hopefully, you drew an dot or circle! Imagine an arrow: if it's going out of the page, we can see the pointy tip of the arrow.

What are some examples of contact forces? Give at least 3.

Answer explanation

Any force that involves contact between objects is a contact force: friction, drag, tension, normal, & spring forces.

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-PS2-5

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.

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.

Which image represents a magnetic field out of the page, and a charged particle moving to the left?

• Left

• Middle

• Right

Answer explanation

Right-hand rule!

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5