Question

During summersault a swimmer bends his body: which one is correct and why? a) increase moment of intertia b) decrease moment of inertia c) decrease angular momentum d) reduce the angular velocity

Answer 1

A swimmer bends his body to decrease moment of inertia. This is because during a somersault, a full rotation is to be performed in a limited amount of time. Thus because moment of inertia is lesser, the body rotates faster and hence able to complete the somersault successfully.

Answer 2

we know that

L = I w

if I decrease, w inceresas

that's why during Summer Sault a swimmer bends his body .