1. The problem statement, all variables and given/known data A marble of moment of intertia 2.3 x 10^-8 kg.m^2 rolls down an incline of vertical height 10cm. It's speed at the bottom is: 1.2m/s 1.4m/s 1.2cm/s 1.4cm/s 2. Relevant equations Well this isn't homework, this is just a worked example question we have. Apparently, the derived formula given is Sqrt(10.g.h / 7) 3. The attempt at a solution The problem is, I don't know how to derive that formula. I missed a few lectures back, which I think this covers. I don't even recognise the phrase 'moment of inertia'. Unfortunately, I don't have a textbook to go over. If it's too difficult to explain over the forums, that's fine, I'll go and visit my professor. But if anyone could point me in the right direction, it would be a huge help. Thanks!