Question

The super-villain pushes a trunk of mass 400 kg (880 lbs) down the ramp shown while the superhero resists. The length of the ramp is 4 meters and the angle θ = 25^o. The villain pushes with a force F_o = 5000 N and the coefficient of kinetic friction between the trunk and the ramp is 0.6. The superhero is unable to stop the trunk but pushes with a force F₁large enough so that the trunk moves down the ramp at constant speed from the top to the bottom of the ramp.

1) How much work is done on the trunk by the villain? Answer in joules

2) What is the increase in thermal energy during this process? Answer in joules.

3) What was the work done on the trunk by the hero during this process? Answer in joules.

4) The struggle takes 25 seconds. What is the average power provided by the super-villain? Answer in watts.

Answer 1