Question

A simple pendulum with a charged bob is oscillating as shown in the figure.Time period of oscillation is T and angular amplitude is $\theta$.If a uniform magnetic field perpendicular to the plane of oscillation is switched on, then :

• A. T will decrease but $\theta$ will remain constant
• B. T will remain constant but $\theta$ will decrease
• C. Both T and $\theta$ will remain the same
• D. Both T and $\theta$ will decrease

Answer 1

Answer: (C)

Both T and $\theta$ will remain the same

Magnetic force is always perpendicular to velocity.So, it will always act in radial direction which will change tension at different points.But time period and $\theta$ will remains unchange.