Hi everyone, I am stuck on two fairly easy questions that I hope someone will be able to help me with. Questions: 1) How much angular impulse must be supplied by the hamstrings to bring a leg swinging at 8 rad/s to a stop, given that the leg's moment of inertia is 0.7 kg-m^2 ? my solution: angular impulse = change in angular momentum Tt = Iw2 - Iw1 (the numbers 2 & 1 are supposed to be subscripts standing for final and initial; I=moment of inertia; w=angular velocity) Tt = 0 - (.7)(8) = -5.6 kg-m^2/s what did I do wrong? 2) A 7.27kg shot makes seven complete revolutions during its 2.5 second flight. If its radius of gyration is 2.54 cm, what is its angular momentum? my solution: H = mk^2w (m=mass; k=radius of gyration; w=angular velocity; H = angular momentum) 7 revolutions = (360degrees x 7)/57.3 = 43.979 rad H = (7.27)(.0254^2)(43.979/2.5sec) = .0825 kg-m^2/s what did I do wrong? thanks.