- #1
student34
- 639
- 21
Homework Statement
A thin and uniform bar has a length of 2.00 m and weighs 12.0 kg. It is rotating from one end on a pivot 5 times every three seconds. What is its kinetic energy?
This is its hint: break the bar up into infinitesimal segments of mass dm and integrate to add up the kinetic energies of all of these segments.
Homework Equations
v = d/t = 20∏m/3s
Ek = 0.5*m*v^2
∫(12kg - 0kg)0.5*v^2dm
The Attempt at a Solution
∫(12kg - 0kg)0.5*v^2dm = (0.5(20∏/3)^3)/3 x 12 = 18374J
But I am way off because the answer is 877J