Aloaded ore car has a mass of 950 kg and rolls on rails with negligible friction. it starts from rest and is pulled up a mine shaft by a cable connected to a winch. the shaft is inclined at 24.0° above the horizontal. the car accelerates uniformly to a speed of 2.00 m/s in 12.5 s and then continues at constant speed. (a) what power must the winch motor provide when the car is moving at constant speed? kw b) what maximum power must the motor provide? kw (c) what total energy transfers out of the motor by work by the time the car moves off the end of the track, which is of length 1,250 m?

Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. which one, if either is correct? a. beryl, because low thermal conductivity results in low heat transfer. b. beryl, because low thermal conductivity results in high heat transfer. d. sapphire, because low thermal conductivity results in high heat transfer. e. neither, because low heat transfer is desirable both in summer and in winter.