Question

A solid sphere of mass M and radius R rolls on a horizontal surface without slipping. The ratio of rotational kinetic energy to total kinetic energy is

• A. 1 : 2
• B. 2 : 5
• C. 2 : 7
• D. 7 : 10

Answer 1

Answer: (C)

2 : 7

Answer 2

$\frac { \text { KE } _ { \text {Rot. } } } { \text { TotalKE } }$ = = $\frac { 2 / 5 } { 1 + 2 / 5 }$ =$\frac { 2 } { 7 }$