Question

If we want to maximise the magnitude of the magnetic force acting on a charged particle moving in a magnetic field. By which of the following statements we can maximise it.
I. Maximize the strength of the magnetic field
II. Minimize the velocity of particle.
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

Magnetic force, $F=qvB$ $sin\theta$ where $\theta$ is the angle between $v$ and $B$

Thus force can be maximizes either by maximizing $v$ or $B$ or $\theta ={90}^o$

Thus only statement $I$ is true and hence option A is correct.