Answer to Question #139001 in Physics for Divyesh Chandra Seharan

Question

A hamster running in an exercise wheel. Typical hamsters are 320 g and can run at speeds of 2.8 m s

-1. The exercise wheel has a moment of inertia about its centre of 0.22 kg m2 and the radius of the wheel is 10.0 cm. How fast should the wheel have been rotating? Treat the hamster as a point mass.

Answer 1

Before the hamster starts running, the exercise wheel is not rotating. Considered as a system, angular momentum must be conserved.

$$L_i=L_f\\L_{wheel}+L_{hamster}=0\\-IΩ + Rmv = 0\\0.22Ω=(0.32)(2.8)(0.1)\\Ω=0.407\frac{rad}{s}$$