Baby with a mass of 11.8 kg bounces up and down in his crib. The crib mattress behaves like a light spring with a force constant of 1050 N/m.
(a) The baby bounces with a frequency that allows him to reach maximum amplitude with minimum effort. What is this frequency (in Hz)?
(b) The baby now bounces high enough to lose contact with the mattress once each cycle, like a trampoline. What is the minimum amplitude of oscillation (in cm) required for this to occur?