Question

If rotational kinetic energy is 50% of translational kinetic energy, then the body is:

• A. Ring
• B. Cylinder
• C. Hollow sphere
• D. Solid sphere

Answer 1

Answer: (B)

Cylinder

Answer 2

$\frac { 1 } { 2 } m v ^ { 2 } \left( \frac { K ^ { 2 } } { R ^ { 2 } } \right) = \frac { 50 } { 100 } \times \frac { 1 } { 2 } m v ^ { 2 }$⇒ $\therefore$ $\frac { K ^ { 2 } } { R ^ { 2 } } = \frac { 1 } { 2 }$

i.e. body will be solid cylinder