2. A football player kicks a ball with a force of 50N. Find the impulse on the ball if his foot stays in contact with the football for 0.01s.
a
3.A hockey player applies an average force of 80N to a 0.25kg hockey puck for a time of 0.2s.
Determine the impulse experienced by the hockey puck.

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?

We have a colorless transparent liquid. it looks like water. we seperated it into a solid and a liquid by evaporration and condention was this a chemichal or a physical seperation a. chemical seperation b. physical seperation

What sort of waves exhibit the doppler effect?