An 80% efficient pump with a power input of 20 hp is pumping water from a lake to a nearby pool at a rate of 1.5 ft3/s through a constant-diameter pipe. the free surface of the pool is 80 ft above that of the lake. determine the mechanical power used to overcome frictional effects in piping.

Amira pulls a 3 pound wagon 4 feet. how much work has she done?

Give an example in which the electrical energy changes to light energy

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?