Question

A ball is attached to a pole by a string. When the pole is rotating,
the distance from the center to the ball is 0.75 m. what is f net if the time for one revolution is 1.10 s and the mass is 2.6 kg? what is the length of the string?

Answer 1

So both forces on the ball is just oposit in direction and same magnitude

Answer 2

Break the tension into two components- the vertical will be Tcos(theta) and the horizontal component will be Tsin(theta). The vertical component will cancel the gravitational force mg and the horizontal will provide the centripetal force.
so you get, Tcos(theta)=mg
and Tsin(theta)=(mv^2)/r
here r=0.75m
divide both the equations and you'll get tan(theta)
now you can find sin(theta) from tan(theta) and hence find the length of the string that is the hypotenuse.
I think this helps you

Answer 3

ps.
theta is the angle between the string and the pole