1. The problem statement, all variables and given/known data A tennis ball is a hollow sphere with a thin wall. It is set rolling without slipping at 4.08 m/s on a horizontal section of a track as shown in the figure below. It rolls around the inside of a vertical circular loop of radius r = 45.8 cm. given radius =0.458m ω= 4.08 2. Relevant equations KE1 + GPE1 = KE2 +GPE2 V = Rω 3. The attempt at a solution I did the algrabra and ended up with Vf = ( (ωR)^2 -4gR)^(1/2) i end up with a negative number.