Question

A diver goes from a layout position (full extension) into a tuck position (knees to chest) in mid-air.

Which of the following describes the change in angular momentum over this period?

Select one:

a. It increases

b. It decreases

c. It does not change

Answer 1

When diver goes from a layout position (full extension) into a tuck position (knees to chest) in mid-air, he chanes the moment of inertia of his body about his axis of rotation. But this change in position does not lead to any external torque to his body about the axis of rotation because the force which he apply do not give any net toque about the axis of rotation, so the angular momentum remains the same. Indeed, the angular velocity of diver changes to keep the angular momentum same.