A disc with moment of inertia I_{1} = 40 kg • m^{2} and angular velocity ω_{1} = 20 rad/s is dropped on to a stationary second disc along the axis of rotation. The second disc has moment of inertia I_{2} = 60 kg • m^{2}. What is the angular velocity of the two discs?

A. 12 rad/s

B. 8 rad/s

C. 4 rad/s

D. 20 rad/s

E. 6 rad/s

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Intro to Angular Collisions concept. You can view video lessons to learn Intro to Angular Collisions. Or if you need more Intro to Angular Collisions practice, you can also practice Intro to Angular Collisions practice problems.

How long does this problem take to solve?

Our expert Physics tutor, Jeffery took 1 minute and 37 seconds to solve this problem. You can follow their steps in the video explanation above.