A mass of 1.5 kg is located at the end of a very light and rigid rod 50cm in length.

Question

The rod is rotating about an axis as its opposite end with a rotational velocity of 5 rad/s.

a. What is the rotational inertia of the system?

b. What is the angular momentum of the system?

Answer 1

rotational inertia = I = m*r^2

m=1.5kg

r=50/100 meter = 0.5 meter

w=5 rad/s

rotational inertia = 1.5*0.5^2 = 0.375 kg-m^2

angular momentum =I*w=1.5*0.5^2*5 = 1.875 kg-m^2/s