Magnetism and AC circuit

A proton is released such that it has an initial speed of 4.0 x 10⁵ m/s from left to right across the page. A magnetic field of 1.2 T is present at an angle of 30° to the horizontal direction (or positive x axis). What is the magnitude of the force experienced by the proton?

• 4.8 x 10^-25 N

• 1.3 x 10^-19 N

• 3.8 x 10^-14 N

• 7.5 x 10³ N

The force on a charged particle created by its motion in a magnetic field is maximum at what angle between the particle velocity and field?

• zero

• 180°

• 90°

• 45°

Assume that a uniform magnetic field is directed into this page. If an electron is released with an initial velocity directed from the bottom edge to the top edge of the page, which of the following describes the direction of the resultant force acting on the electron?

• out of the page

• to the right

• to the left

• into the page

A stationary positive charge +Q is located in a magnetic field B, which is directed toward the right as indicated. The direction of the magnetic force on Q is:

• rightward

• upward

• downward

• no magnetic force

What would increase the strength of an electromagnet?

• Increasing the amount of current flowing through the wire.
• Inserting a wooden core inside the coil
• Changing the direction of the current
• Decreasing the number of coils of wire

Tags

NGSS.MS-PS2-3

Which direction is the North Pole of this electromagnet?

• Right

• Left

• Up

• Down

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.

Tags

NGSS.HS-PS2-5

The period of a wave is

• the same as frequency
• time required to complete one cycle
• expressed in amperes
• none of the above

There is a magnetic force on a particle. It is possible that the particle is:

• uncharged.

• stationary.

• moving in the direction of the magnetic field.

• not part of a wire.

A copper wire of length 25 cm is in a magnetic field of 0.20 T. If it has a mass of 10 g, what is the minimum current through the wire that would cause a magnetic force equal to its weight?

• 1.3 A

• 1.5 A

• 2.0 A

• 4.9 A