question_answer

A tennis ball (treated as hollow spherical shell) starting from O rolls down a hill. At point A the ball becomes air borne leaving at an angle of \[{{30}^{0}}\] with the horizontal. The ball strikes the ground at B. What is the value of the distance AB? (Moment of inertia of spherical shell of mass m and radius R about its diameter \[=\frac{2}{3}{{\operatorname{mR}}^{2}})\] [JEE ONLINE 22-04-2013]

A)         1.87 m           

B)        2.08 m

C)   1.57 m           

D)        1.77 m

Correct Answer: B

Solution :

[b] of the tennis ball on the surface of the earth or ground

(where k = radius of gyration of spherical shell)

Horizontal range