A resistance coil, wired to an external battery, is placed inside a thermally insulated cylinder fitted with a frictionless piston and containing an ideal gas. A current $i=240 \mathrm{~mA}$ flows through the coil, which has a resistance $R=550 \Omega$. At what speed $v$ must the piston, of mass $m=12 \mathrm{~kg}$, move upward in order that the temperature of the gas remains unchanged?