1. Determine the moment-of-inertia in kg/m^2 of a solid disk 0.51 m in diameter, having a mass of 5.0 kg. 2. I=mr^2 3. I thought the formula was I = mr^2. Mass = 5kg and the radius = .255m, but when I enter the answer of .325 it is incorrect. Am I using the correct formula? Thanks.