Astudent and the waxed skis he is wearing
have a combined weight of 850 newtons. the skier
travels down a snow-covered hill and then glides
to the east across a snow-covered, horizontal
surface.
53 determine the magnitude of the normal force
exerted by the snow on the skis as the skier
glides across the horizontal surface.

Acoal-fired plant generates 600 mw of electric power. the plant uses 4.8 x 10^6 kg of coal each day, and the heat of combustion of coal is 3.3x 10^7 j/kg. the steam that drives the turbines is at a temperature of 300° c, and the exhaust water is at 37° c. (a) what is the overall efficiency of the plant for generating electric power? (b) how much thermal energy is exhausted each day? (c) what is the change in entropy of the universe for this heat engine? (d) using the same heat reservoirs, what is the maximum possible (carnot) efficiency for a heat engine?

The difference between a red shift and a blue shift has to do with wavelength frequency. t or f

The mass of a bowling ball is 10 kg and the mass of a ping pong ball is 0.015 kg. if the two objects are 5 meters apart, what is the gravitational force ?