A resistance coil connected with wire to an external battery is placed inside an adiabatic cylinder fitted with a frictionless piston of area of cross-section 5×10−4m2of mass 5 kg and containing an ideal gas. A current 0.2 A flows through the coil which has a resistance 500Ω . The constant speed v with which the piston move upwards in order that the temperature of the gas remains unchanged is (P0 = 105 N/m2, g = 10 m/s2)