When the depth of the rock below the surface is 0 m, it has not moved since it was released at the surface. No work has been done and there is zero kintic energy.
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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.
2 answers
There are 3 portions. The next one is at 0.50 m and the last one is when the rock is at 1.0 m.