Okay, the original problem was:
For the solid sphere in the figure calculate the translational speed of the center of mass and the magnitude of the translational acceleration of the center of mass at the bottom of the incline of height h = 3 m and angle θ = 30°.
I finished this part of the problem, but there is an additional part that I am struggling with:
What if a solid cylinder of mass M = 2.7 kg, radius R = 15 cm, and length L = 30 cm, is rolling down from rest instead? With h = 1.6 m, and x = 3.9 m, what is the center of mass velocity when the cylinder reaches the bottom? (Use g = 9.80 m/s2.)
I know that the moment of inertia for a cylinder is I = .5MR^2, but when I worked that out, my final answer was 3.96 and webassign gave me this response:
"This answer would apply if the solid cylinder were, instead, a hollow cylinder whose mass is all at a distance R from the cylinder axis." I can't figure out what i'm doing wrong. Please help!
Tags: