A ballerian spins initially at 1.5rev/s when arms are extended. She then draws in her arms to her body and her moment of intertia is .88kg m^2 and her angular speed increases to 4.0rev/s. Determine the network she did to increase her angular speed? To find moment of inertia was pretty simple i used IW=I2W2 for and solved for I, I(1.5rev/s * 2PI rad/1rev)=(.88kg m^2)(4.0rev/s * 2PI rad/1rev) and i got 2.3kg M^2. Ok this was fairly easy. But for Net WORK, how do i calculate it ? I am not to sure which equation to use.... Is it Sum of Net WORK= I2W2-I1W1, where W is squared?