Question

A simple pendulum is moving up as its velocity vector is pointing in the direction of $E$.
Identify the direction of the net force acting on the pendulum?

• A. $A$
• B. $B$
• C. $C$
• D. $D$
• E. $E$

Answer 1

The correct option is C $C$

The centripetal force acting on the bob at that instant $F_c=\frac{m{v}^2}{l}$

$T=mgcos\theta +\frac{m{v}^2}{l}$

Thus tension in the string will balance the sum of centripetal force and $mgcos\theta$ and hence the net force acting on the bob is $mg$ $sin\theta$ in the direction as shown in the figure.

Thus the net force acts in the direction of C.