JEE Main 2022 · 24 Jun · Shift 2 · Physics Q33

PhysicsSingle correct+4 / -1Question 33 of 90

A stone of mass m, tied to a string is being whirled in a vertical circle with a uniform speed. The tension in the string is

the same throughout the motion.

minimum at the highest position of the circular path.

minimum at the lowest position of the circular path.

minimum when the rope is in the horizontal position.

Answer and worked solution

Official answer: B

Radial equation (uniform speed, $\theta$ measured from the lowest point): $T-mg\cos\theta=\dfrac{mv^2}r$ , so $T=\dfrac{mv^2}r+mg\cos\theta$ .

Minimum where $\cos\theta=-1$ , at the highest point.

(B)

Topics:Motion in a vertical circle Circular motion dynamics

JEE Main 2022 · 24 Jun · Shift 2, Physics question 33