science

A tired squirrel (mass of 1 kg) does push-ups by applying a force to elevate its center-of-mass by 5 cm. Estimate the number of push-ups that a tired squirrel must do in order to do a approximately 5.0 Joules of work.

 $W_{pushup}=F_{pushup} d \\ F_{pushup} = m g = (1kg)(9.8m/s^2) = 9.8N\\ W_{pushup}=(9.8N)(0.05m) = 0.49Joules$

$\dfrac {5}{0.49} \approx 10.2 \\ \mbox{So }10 \mbox{ pushups is about }5 \mbox{ Joules of work.}$