# Question

Imagine that you swing about your head a ball attached to the end of a string. The ball moves at a constant speed in a horizontal circle.

(a) Can the string be exactly horizontal? Why or why not?

(b) If the mass of the ball is 0.250 kg, the radius of the circle is 1.50 m, and it takes 1.20 s for the ball to make one revolution, what is the ball’s tangential speed?

(c) What centripetal force are you imparting to the ball via the string?

(a) Can the string be exactly horizontal? Why or why not?

(b) If the mass of the ball is 0.250 kg, the radius of the circle is 1.50 m, and it takes 1.20 s for the ball to make one revolution, what is the ball’s tangential speed?

(c) What centripetal force are you imparting to the ball via the string?

## Answer to relevant Questions

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