Please hurry, being timed. and no links !!! A ball weighing 10 kg rolls down a frictionless incline with a 50 degree angle to the horizontal. if the balls initial velocity was 0 m/s, how much does the mechanical energy of the system change by the time the ball reaches its destination.
A. increases by 12%
B. increases by 58%
C. decreases by 12%
D. does not change

4r-134a enters the condenser of a residential heat pump at 800 kpa and 50°c at a rate of 0.022 kg/s and leaves at 750 kpa subcooled by 3°c. the refrigerant enters the compressor at 200 kpa superheated by 4°c determine (a) the isentropic efficiency of the compressor, (b) the rate of heat supplied to the heated room, and (c) the cop of the heat pump. also, determine (d) the cop and rate of heat supplied to the heated room if this heat pump operated on the ideal vapor-compression cycle between the pressure limits of 200 and 800 kpa. (0.757, 4.37 kw, 5.12, 6.18, 3.91 kw)