Question
A gymnast doing a forward flip lands on the mat and exerts a 500-N · m torque to slow and then reverse her angular velocity. Her initial angular velocity is 10.0 rad/s, and her moment of inertia is $0.050 \textrm{ kg} \cdot \textrm{m}^2$.(a) What time is required for her to exactly reverse her spin? (b) What is unreasonable about the result? (c) Which premises are unreasonable or inconsistent?

a) 2ms

b) 2ms is too short

c) The moment of inertia is too small.

Solution Video