physics help please?

Test Preparation SAT Subject Test Preparation
1

<p>I don't know how to do this, could someone explain or show me how?</p>

<p>A ball on the end of a string is cleverly revolved at a uniform rate in a vertical circle of radius 85.0 cm Its speed is 3.90 m/s and its mass is 0.300 kg.</p>

<p>(a) Calculate the tension in the string when the ball is at the top of its path.
N
(b) Calculate the tension in the string when the ball is at the bottom of its path.
N</p>

2

<p>I could be wrong but</p>

<p>Top is Fc - mg
Bottom is Fc + mg</p>

<p>Fc = (mv^2) / r (You obviously know that)</p>

<p>The reason for this is the weight at the top aids in keeping it in the circle so the tension is less.</p>