PLEASE HELP 25 PTS A 91 kg hockey player is skating at 5.50 m/s. Another hockey player of equal mass, moving at 8.1 m/s in the same direction, hits him from behind. They slide off together. a. What is the total mechanical energy and momentum of the system before the collision? b. What is the velocity of the two hockey players after the collision? c. How much was the system’s kinetic energy decreased in the collision?

Which units can be used to measure length or distance? check all that apply. gram meter kilometer liter inch

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.

Assume this car is driven off a cliff . how many arrows of force need to be drawn in the free body diagram? assume no air resistance -five -one -three -four