Honors Lab

Both sections read this. It will help Section 2 write reports and Section 3 understand what they'll be doing Thursday

All the PE initial should ( i.e. is expected to) become KE at the bottom. KE has both rotational and translational (linear) parts. Rotational KE is I omega ^2/2 and

I for a sphere is 2MR^2/5 so we have

KE rotational = 2MR^2/5 times omega ^2 /2 or
KE rotational = 2M(R omega)^2/5 /2 and of course R omega = v so

rotational KE is 2Mv^2/5 /2 = Mv^2/5.

Translational KE is Mv^2/2 so

total KE is (1/5 +1/2) Mv^2 = .7 Mv^2.

From this you should be able to find your expected value for v given your initial PE (i.e. Mgh).

This is already too much help. You should be able to r the rest now. Remember, discussion should be more than answering lab sheet questions. You must decide if our hypothesis about total KE is correct.Thus, you must find percent error using either measured vs expected v or measured vs expected KE.