In: Physics
Two balls (solid spheres) have the same radius and the same rotational kinetic energy. If the ratio of their masses is
| m1 |
| m2 |
=
| 4 |
| 1 |
, what is the ratio of their angular velocities?
Mass of the first ball = m1
Radius of the first ball = R1
Moment of inertia of the first ball = I1 = 2m1R12/5
Angular velocity of the first ball =
1
Rotational kinetic energy of the first ball = E1

Mass of the second ball = m2
Radius of the second ball = R2
Moment of inertia of the second ball = I2 = 2m2R22/5
Angular velocity of the second ball =
2
Rotational kinetic energy of the second ball = E2

Ratio of the masses of the balls = m1/m2 = 4/1
The balls have the same radius.
R1 = R2
The balls have the same rotational kinetic energy.
E1 = E2









Ratio of the angular velocities of the balls is given by,
