a stone attached to the end of elastic string is whirled around in a circular path of radius 20cm if the stone makes 15 complete revolution in 5 seconds, calculate its angular and linear velocities.

I don't know the answer

ω = 15rev/5sec = 3rev/s = 6π rad/s

v = 20*2π cm/rev * 3rev/s = 120π cm/s

What's the answer with it's calculations

To calculate the angular and linear velocities of the stone, we need to use the formula:

Angular velocity (ω) = 2π * frequency (f)
Linear velocity (v) = ω * radius (r)

First, let's calculate the frequency. The stone completes 15 revolutions in 5 seconds, so the frequency (f) can be calculated as:

Frequency (f) = Number of revolutions / Time
= 15 / 5
= 3 Hz

Next, we can use the formula for angular velocity to calculate ω:

Angular velocity (ω) = 2π * frequency (f)
= 2π * 3
= 6π rad/s

Now, we can use the formula for linear velocity to calculate v:

Linear velocity (v) = ω * radius (r)
= 6π * 20 cm/s
= 120π cm/s

So, the angular velocity of the stone is 6π rad/s, and the linear velocity is 120π cm/s.