Aspring that is stretched by hanging a 5kg mass. it's equilibrium length was 0.5 meters. now the length of the spring is 1.6 meters. what is the spring constant?

Calculate the amount of heat produced when 18000 coulombs of charge is transferred in one hour through a potential difference of 50v

An insulated 40 ft^3 rigid tank contains air at 50 psia and 120°f. a valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 psia. the air temperature during this process is kept constant by an electric resistance heater placed in the tank. determine the electrical work done during this process.

During the past 150 years in the united states, how did energy consumption compare to population growth