Question

Rocket Man has a propulsion unit strapped to his back. He starts from rest on the ground, fires the unit, and accelerates straight upward. At a height of 18 m, his speed is 5.1 m/s. His mass, including the propulsion unit, has the approximately constant value of 138 kg. Find the work done by the force generated by the propulsion unit.

Answer 1

Answer: 26213 joules

Step-by-step explanation:

At 18m the GPE = mgh = (138)(9.81)(18) = 24368 J

At 18 m the KE = 1/2mV^2= (0.5)(138)(5.1)^2 = 1795 J

Total mechanical energy = 24368+ 1795= 26213 J = work done