The mass m1 is 4 kg. There is friction on the surface. When released, mass m2 will acceleration downward. 1.What tension force makes the acceleration of mass m1 equal to 3 m/s/s?
2.What mass m2 makes the acceleration of mass m2 equal to 3 m/s/s?

Identify the theory that can be used to explain each phenomenon. answers diffraction: wave theory interference: wave theory reflection: both particle and wave theories refraction: both particle and wave theories

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?

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)