A rock is tossed straight up with a speed of 20 m/s. When it returns, it falls into a hole 10 m deep. A. What is the rock's velocity as it hits the bottom of the hole?
B. How long is the rock in the air, from the instant it is released until it hots the bottom of the hole?

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 10.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.90 m/s; (b) he is then lifted at the constant speed of 4.90 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 68.0 kg rescue by the force lifting him during each stage?

What is a possible result of higher air temperature caused by global warming

Photons with the highest energy have the longest period