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## Homework Statement

A golf ball with mass m = 0.05 kg is tied to a massless string of length L = 0.28 m. The ball is made to swing in a circle such that the string is horizontal throughout the motion. The ball makes one revolution every t = 2.1 s.

m = 0.05 kg

L = 0.28 m

t = 2.1 s

## Homework Equations

F

_{net}= mv

^{2}/r

## The Attempt at a Solution

**(a)**What the magnitude of the tension in the string, F

_{t}in Newtons, while it spins?

First, I made it so that one revolution would occur at the bottom of the circle which is created by the ball swinging, so that it would be a little easier mathematically.

I identified F

_{net}as the Tension of the string on the ball pulling upward (T

_{SB}) minus the weight of the Earth on the ball (W

_{EB}). The rearranged equation looks like this:

T

_{SB}- W

_{EB}= mv

^{2}/r

Then I rearranged it to look like this:

T

_{SB}= mv

^{2}/r + W

_{EB}

Since Weight = mg...

T

_{SB}= mv

^{2}/r + mg

With that, I plugged in my numbers:

T

_{SB}= (.05kg)v

^{2}/(.14m)+ (.05kg)(9.8 m/s

^{2})

I got the radius by dividing the length by two...though I'm not sure if this is right. Plus, there doesn't seem to be any information about the velocity. How would I go about finding this? Would I use a = ΔV/t?

**(b)**The string breaks suddenly. How fast does the golf ball fly away, v in m/s?

What accounts for the string breaking? How do I know which direction the string is flying in? Would it matter in this case if the string was flying in a positive direction or a negative direction?