Question

Eva twirls a stone attached to a string 2.0 meters long in a horizontal circle. At what speed must the stone move for its centripetal acceleration to be equal to the acceleration due to gravity (9.8 m/s^2)? Round your answer to the nearest tenth. m/s

Answer 1

Answer:

4.43m/s

Explanation:

The centripetal acceleration is expressed as;

a = v²/r

v is the speed

r is the radius = 2.0m

centripetal acceleration = 9.8m/s²

Get the speed v;

v² = ar

v² = 2.0 * 9.8

v²= 19.6

v = √19.6

v = 4.43m/s

Hence the speed of the stone must be 4.43m/s