In which situation is the magnetic force nonzero?

[McAfee]

Homework Statement

A particle moves through a magnetic field. In which situation is the magnetic force nonzero?

A. The charge is zero and the particle is moving perpendicular to the magnetic field.
B. The charge is negative and the particle is moving in the direction of the magnetic field.
C. The charge is zero and the particle is moving in the direction of the magnetic field.
D. The charge is zero and the particle is moving in the direction opposite that of the magnetic field.
E. The charge is positive and the particle is moving in the direction opposite that of the magnetic field.
F. The charge is positive and the particle is moving perpendicular to the magnetic field.

Homework Equations

F= qv x B

The Attempt at a Solution

I have ruled out A, C, and D. I think the answer is F because it will be equal to 1 then.

 

[tiny-tim]

Hi McAfee!

A particle moves through a magnetic field. In which situation is the magnetic force nonzero?

A. The charge is zero and the particle is moving perpendicular to the magnetic field.
B. The charge is negative and the particle is moving in the direction of the magnetic field.
C. The charge is zero and the particle is moving in the direction of the magnetic field.
D. The charge is zero and the particle is moving in the direction opposite that of the magnetic field.
E. The charge is positive and the particle is moving in the direction opposite that of the magnetic field.
F. The charge is positive and the particle is moving perpendicular to the magnetic field.
…
I have ruled out A, C, and D. I think the answer is F because it will be equal to 1 then.

Yes, that's correct …

the others are 0 either because v is 0, or because v is parallel or anti-parallel to B (sinθ = 0)

 

[McAfee]

Thanks tiny-tim for confirming and congrats on the 2011 PF Award. People like you are really helpful. I wish you best of luck in your future.