A 70kg boy is running at about 9m/s. find its kinetic energy

Several processes form metal ore. match each process to its description. volcanic activity weathering hydrothermal energy rocks break down as they interact with air and water. arrowright density differences and other factors cause metals to concentrate in igneous rocks. arrowright seawater heats up from contact with hot rock, and metals dissolve in it. the water rises and contacts cooler water, causing metal ores to settle on the ocean floor. arrowright

50 g of ice at 0°c is dropped in a beaker containing 100 g of water at 0°c. what will be the contents of the beaker after 5 hours? assume that the room temperature is 0°c.

A23 kg log of wood begins from rest, 300 m up a sluice (a water track used to transport logs, think of it as an inclined plane with negligible friction) inclined at 20° to the horizontal. after it reaches the flat waterway at the bottom it collides elastically with a 100 kg block of wood initially at rest near the base of the incline. (a) how long does it take the 23 kg log to travel down the incline? (b) what is the speed of the 23 kg log at the bottom of the incline? (c) what are the velocities of both blocks of wood after the collision? (d) what is the total kinetic energy before the collision? (e) what is the kinetic energy of the 23 kg log after the collision? (f) what is the kinetic energy of the 100 kg block of wood after the collision? (g) what is the total kinetic energy after the collision? (h) compare the total initial and total final kinetic energies. is this consistent with what you would expect for elastic collisions? explain!