Thursday
March 23, 2017

Post a New Question

Posted by on Tuesday, May 10, 2011 at 7:57pm.

A turntable with a moment of inertia of 0.029 kg*m^2 rotates feely at 2.8 rad/s. A circular disk of mass 270 g and diameter 20 cm, and initially not rotating, slips down a spindle and lands on the turntable.

a) Find the new angular speed.
b) What is the change in kinetic energy?

  • Physics - , Tuesday, May 10, 2011 at 9:50pm

    a) Angular momentum about the spindle is conserved.

    Iturntable*w1 = (Iturntable+Icd)w2

    Solve for the final angular velocity w2.

    b) (1/2)*Iturntable*w1^2 - (1/2)(Iturntable + Icd)*w2^2

    The formula for the compact disc moment of inertia Icd is:
    Icd = (1/2)Mcd*Rcd^2

Answer This Question

First Name:
School Subject:
Answer:

Related Questions

More Related Questions

Post a New Question