A solid sphere is in rolling motion. In rolling motion a body prosseses translational kinetic energy `(K_(t))` as well as rotational kinetic energy `(K_(r))` simutaneously. The ratio
`K_(t) : (K_(t) + K_(r))` for the sphere is

Options

A. `7: 10`
B. `5: 7`
C. `10: 7`
D. `2: 5`

Answer

B

Explanation

`(K_(t))/(K_(t) + K_(r)) = ((1)/(2) xx mv^(2))/((1)/(2) mv^(2) [1+ (k^(2))/(R^(2))])= (1)/(1+ (2)/(5)) = (5)/(7)`