Q. A baby bounces up and down in her crib. Her mass is 10.5 kg, and the crib mattress can be modeled as a light spring with force constant 716 N/m.
(a) The baby soon learns to bounce with maximum amplitude and minimum effort by bending her knees at what frequency?
(b) If she were to use the mattress as a trampoline losing contact with it for part of each cycle. What minimum amplitude of oscillation does she need?