Which equation can be used to calculate the normal force on an object if you know the speed of the object, the coefficient of kinetic friction, and the force
of kinetic friction on the object?
Ffriction
O A. FN
HA
us
B. FM
Ffriction
νμ,
C. FN
Ffriction
D. Fn = M Ffriction

What is the average speed of a car that travels 40 mph for 1 hour and 60 mph in another hour?

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)

If a star is moving toward earth, it is