Part A) A 2.2 kg rock is released from rest at the surface of a pond 1.8 m deep. As the rock falls, a constant upward force of 5.0 N is exerted on it by water resistance. Let y=0 be at the bottom of the pond. Calculate the nonconservative work, Wnc , done by water resistance on the rock, the gravitational potential energy of the system, U , the kinetic energy of the rock, K , and the total mechanical energy of the system, E , when the depth of the rock below the water's surface is 0 m.

Question

Part A) A 2.2 kg rock is released from rest at the surface of a pond 1.8 m deep. As the rock falls, a constant upward force of 5.0 N is exerted on it by water resistance. Let y=0 be at the bottom of the pond. Calculate the nonconservative work, Wnc , done by water resistance on the rock, the gravitational potential energy of the system, U , the kinetic energy of the rock, K , and the total mechanical energy of the system, E , when the depth of the rock below the water's surface is 0 m.
Part B) What is the Wnc of the water resistance on the rock, U, K, and E when the rock is 0.50 m below the surface?
Part C) What is the Wnc of the water resistance on the rock, U, K, and E when the rock is 1.0 m below the surface?

drwls · Answer

Someone will gladly critique your work.

Nonconservative work done is the product of the water resistance force and the distance it has fallen.

They have not mentioned the density of the rock. There will be a buoyancy force on the rock that should be considered, so some of the answers they want may not be the correct ones