Question

A 1.5 kg spherical ball is has a radius of 50 cm is rotating with angular velocity of 12 revolutions per minute. Determine the rotational kinetic energy

Answer 1

K.E = 0.0075 J

Step-by-step explanation:

Given data:

Mass of the ball = 1.5 kg

radius, r = 50 cm = 0.5 m

Angular speed, ω = 12 rev/min = (12/60) rev/sec = 0.2 rev/sec

Now,

the kinetic energy is given as:

K.E =
`K.E=(1)/(2)I\omega^2`

where,

I is the moment of inertia = mr²

on substituting the values, we get

`K.E=(1)/(2)*1.5*0.5^2*0.2^2`

or

K.E = 0.0075 J