Use the law of conservation of momentum to determine the answer to the flowing question: In this group, there are two hockey pucks, both with a mass of 0.25 kg. One is traveling at 2 m/s.
The other is at rest. What is the momentum of this group of objects?

In automobile steering wheel is shown what is the ideal mechanical advantage blank? if the ama is eight what is the efficiency of the steering wheel?

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?