Asked by Emma
A 15 kg uniform disk of radius R = 0.25 m has a string wrapped around it, and a m = 3.3 kg weight is hanging on the string. The system of the weight and disk is released from rest.
When the 3.3 kg weight is moving with a speed of 2.1 m/s, what is the kinetic energy of the entire system?
When the 3.3 kg weight is moving with a speed of 2.1 m/s, what is the kinetic energy of the entire system?
Answers
Answered by
Crake
This isn't my work, so no credit goes to me. Also, we're probably in the same class.
"Remember that a = αR, or α = a/R
Solve for acceleration by using vf2=vi2+2ax (vf=2.2, vi=0, x=(answer in part b))
That gives you the linear a… we want angular acceleration so we just divide our linear acceleration by the radius:
((2.1)^2)/(2*0.5*(2.1^2)*(3.3+(.5*15))/(3.3*9.8))/0.25
= 11.978"
"Remember that a = αR, or α = a/R
Solve for acceleration by using vf2=vi2+2ax (vf=2.2, vi=0, x=(answer in part b))
That gives you the linear a… we want angular acceleration so we just divide our linear acceleration by the radius:
((2.1)^2)/(2*0.5*(2.1^2)*(3.3+(.5*15))/(3.3*9.8))/0.25
= 11.978"
Answered by
Crake
No, we probably aren't in the same class. I take that back. However, my answer should still be right. It should be in rad/s^2 though: 11.978 rad/s^2