Answer
$W_{propulsion}=23024.8J$
Work Step by Step
1) Find the net work done on Rocket Man
We know $m=136kg$, $v_0=0$ and $v_f=5m/s$. The net work done on Rocket Man during the rise is $$\sum W=\frac{1}{2}m(v_f^2-v_0^2)=1700J$$
2) This net work is made up of 2 works: $\sum W=W_{propulsion}-W_{gravity}$
- $W_{propulsion}$ is the work done by the propulsion unit.
- $W_{gravity}$ is the work done by gravitational force, which opposes the motion.
We know $W_{gravity}=mgh=136\times9.8\times16=21324.8J$
Therefore, $$W_{propulsion}=\sum W+W_{gravity}=23024.8J$$
