Homework Statement
How much torque is needed to change the speed of spinning rate of a 3.50 kg sphere with a radius of 7.50 m from 900. rpm to 200. rpm in 3.0 s? [-1924 -1.92 x 103 Nm]
Homework Equations
t = I * α
I = (2/5)mr^2
t = F * r
The Attempt at a Solution
just can't get a crack at...