Question

A boy tied an 80 grams stone to a string which he rotated to a circular motion with

a diameter of 100 mm. Compute the pull exerted on the string by the stone if it got

loose leaving at a velocity of 25m/sec

Answer 1

Mass of the body(m) = 80 g = 0.08 kg

Diameter of circular motion = 100 mm = 0.01 m

Radius = 0.005 m

Tangential velocity = 25 m/s

Centripetal Force = $\dfrac{mv^2}{r}=\dfrac{0.08\times625}{0.005}=10000\space N$

Pull Exerted on string = 10000 N