In the absence of external torque for a body revolving about any axis, the quantity that remains constant is

Options

A. kinetic energy
B. potential energy
C. linear momentum
D. angular momentum

Answer

D

Explanation

In the absence of external torque for a body revolving about any axis , the angular momentum remains constant . This is known as law of conservation of angular momentum
`vectau = (d vecL)/(dt)`
As `vectau = 0 therefore (dvecL)/(dt) =0` or `vecL = ` constant