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If the speed of a charged particle moving through a magnetic field is increased, then the radius of curvature of its trajectory will ______.

Asked in RS Academy GUJCET booklet · Circular motion: radius, period and energy

Answer: (2) increase

Step-by-step solution

Idea: the magnetic force supplies the centripetal force for the circular path, qvB=(mv²)/r.

Solving for the radius: r=(mv)/(qB).

With the charge, the mass and the field fixed, r is proportional to the speed.

So increasing the speed increases the radius of curvature, while the period T=(2π m)/(qB) stays exactly the same.

Why the other options are wrong

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