Suppose that a heat engine takes 3.0 x 10^4 j of heat from the high-temperature reservoir to produce 2.0 x 10^4 j of mechanical work. what is the efficiency of this engine? how much waste heat does it produce?

Awater-filled u-tube manometer is used to measure the pressure inside a tank that contains air. the water level in the u-tube on the side that connects to the tank is 5 ft above the base of the tank. the water level in the other side of the u-tube (which is open to the atmosphere) is 2 ft above the base. determine the pressure within the tank.