Question

A student sits motionless on a stool that can turn friction-free about its vertical axis (total rotational inertia I). The student is handed a spinning bicycle wheel, with rotational inertia I1, that is spinning about a vertical axis with a counterclockwise rotational velocity ω0. The student then turns the bicycle wheel over (that is, through 180∘). Determine the final rotational velocity acquired by the student. Express your answer in terms of the variables

Answer 1

Answer:

Explanation:

The problem can be solved with the help of conservation of angular momentum.

Initial angular momentum

= I₁ω₀

When wheel is turned by 180 degree , its angular momentum becomes

- I₁ω₀ .

So total angular momentum

=  - I₁ω₀ . + I W where W is angular velocity of student .

Applying conservation of angular momentum

=I₁ω₀= - I₁ω₀ +I W

2 I₁ω₀ = I W

W = 2 I₁ω₀  /  I