Fernando is an engineer at an amusement park who is experimenting with changed to the set up fir a magnetic roller coaster ride. In one ride, there are two identical roller coaster cards (red and yellow) that start on opposite sides of a large magnet located in the center of the station. He moves both cars, so each car ends up one space farther away from the large magnet. How did the potential energy of the two cars change? Did the potential energy of one car change more than the other? Why do you think so?

How much work would a child do while puling a 12-kg wagon a distance of 3m with a 22 n force directed 30 degrees with respect to the horizontal? (a) 82j (b) 52j (c) 109j (d) 95j

According to social exchange theory, altruistic behaviors benefit the individual who performs them.

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kpa and 17°c. this system uses a regenerator as well as reheating and intercooling – the intercooler returns the air to the inlet temperature. the pressure ratio across each compressor is 4 ; 300 kj/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°c. determine the system’s thermal efficiency. assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature. (0.378)