Question

A mass of 5 kg is moving along a circular path of radius 1 m. If the mass moves with 300 revolutions per minute, its kinetic energy would be.

• A.
• B.
• C.
• D. 0 J

Answer 1

Answer: (A)

Answer 2

Here,

Mass, m = 5kg, Radius, R = 1 m

The angular speed is given by

The linear speed is

Kinetic energy, $\mathrm { k } = \frac { 1 } { 2 } \mathrm { mv } ^ { 2 }$

$\mathrm { K } = \frac { 1 } { 2 } \times ( 5 \mathrm {~kg} ) \left( 10 \pi \mathrm { ms } ^ { - 1 } \right) ^ { 2 } = 250 \pi ^ { 2 } \mathrm {~J}$