Q. A stone is tied at one ends of a $5 m$ long string and whirled in a vertical circle. The minimum speed at the top required to just cross this position is

1961 205 System of Particles and Rotational Motion Report Error

A

$5 m / s$

36%

B

$57 m / s$

35%

C

$7 m / s$

17%

D

$75 m / s$

11%

Solution:

$v = g r = 9.8 \times 5 = 7 m / s$