A ball on a string is swung around in a horizontal circle. The centripetal force that holds the ball in its circular path is the .

0.60 N, towards the centre of the circle

Explanation:

The tension in the string acts as centripetal force to keep the ball in uniform circular motion. So we can write:

(1)

where

T is the tension

m = 0.015 kg is the mass of the ball

is the angular speed

r = 0.50 m is the radius of the circle

We know that the period of the ball is T = 0.70 s, so we can find the angular speed:

And by substituting into (1), we find the tension in the string:

And in an uniform circular motion, the centripetal force always points towards the centre of the circle, so in this case the tension points towards the centre of the circle.

Explanation: