A 2.0 kg rock is thrown from the top of a hill 60.0 m above sea level (the ravine) using a
catapult. The rock leaves the catapult with a speed of 10.0 m/s. The rock lands on the
ground that is 40.0 meters below sea level. Calculate the speed of therock just before it
contacts the ground (the ground is base level). Hint: use the conservation of mechanical
energy equation.