Question

What should one do to maximize the magnitude of the magnetic force acting on a charged particle moving in a magnetic field?
I. Maximize the strength of the magnetic field
II. Minimize the particles velocity
III. Ensure that the particle is moving in the same direction as the magnetic field lines.

• A. I only
• B. I and II only
• C. I and III only
• D. II and III only
• E. I, II, and III

Answer 1

Answer: (A)

I only

Magnitude of magnetic force $F$ ,acting on a charged particle $q$ moving with velocity $v$ in a magnetic field of strength $B$ is given by ,

$F=qvB\sin \theta$ ,

where $\theta =$ angle between $v$ and $B$ ,

it is clear from this relation force will be maximized , when magnetic field strength $B$ is maximum .

if we minimize the velocity $v$ , force $F$ will also be minimized , and if particle moves in the direction of field then $\theta =0$ which gives

$F=qvB\sin 0=0$