Question

a ball at the end of a string is whirled in a horizontal circle. if it takes 2 seconds to make a revolution and the strong length is 2 m , how fast is the ball moving ? How much is it being accelerated

Answer 1

You can calculate the speed of the ball by the distance it travels divided by the time.

Length of string = 2m

Circumference of circle = 2*radius*π = 4*pi = ~12.6 meters

Speed = distance/time = 12.6m/2s = 6.28m/s

Acceleration = V²/R where the velocity at any one point is the same as the speed.

acceleration = (6.28)²/2 = ~19.72m/s²