A6 kilogram concrete block is dropped from the top of a tall building. the block has fallen a distance of 55 meters and has a speed of 30 meters per second when it hits the ground. a. at the instant the block was released, what was its gravitational potential energy? b. calculate the kinetic energy of the block at the point of impact. c. how much mechanical energy was "lost" by the block as it fell? d. explain what happened to the mechanical energy that was "lost" by the block.

Asilver dollar is dropped from the top of a building that is 1324 feet tall. use the position function below for free-falling objects. s(t) = −16t2 + v0t + s0 (a) determine the position and velocity functions for the coin. s(t) = v(t) = (b) determine the average velocity on the interval [1, 2]. ft/s (c) find the instantaneous velocities when t = 1 second and t = 2 seconds. v(1) = ft/s v(2) = ft/s (d) find the time required for the coin to reach the ground level. (round your answer to three decimal places.) t = s (e) find the velocity of the coin at impact. (round your answer to three decimal places.) ft/s