A car is skidding out of control on a horizontal icy (frictionless) road. It has a mass of 2000 kg and it is headed directly at Lois Lane at a speed of 45.0 m/s. When the car is 200 m from her, Superman begins to exert a steady force on the car, F, relative to the horizontal with a mag-
nitude of 1.30 X 10^4N (he's a strong dude) at a down-
ward angle of 30°. Was Superman correct? Was this force enough to stop the car before hitting Lois?

Aplane takes off from an airport and flies to town a, located d1 = 215 km from the airport in the direction 20.0° north of east. the plane then flies to town b, located d2 = 230 km at 30.0° west of north from town a. use graphical methods to determine the distance and direction from town b to the airport. (enter the distance in km and the direction in degrees south of west.)

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?

Complete the sentence to describe the law of conservation of energy. the law of conservation of energy states that energy cannot be created or , but it can be