A Carnot engine operates between two reservoirs of temperatures $900\mathrm{K}$  and $300\mathrm{K}$ . The engine performs $1200\mathrm{J}$  of work per cycle. The heat energy (in J) delivered by the engine to the low temperature reservoir, in a cycle is

Two moles of helium gas are taken over the cycle ABCDA as shown below in P-T diagram. Assuming the gas to be ideal, the work done on the gas in taking from A to B is

Heat is supplied to an ideal monoatomic gas at constant pressure. The ratio of

An ideal engine whose efficiency is 40%, receives heat at 500 K. If required efficiency is 50%, then intake temperature for the same exhaust temperature is

Choose the correct statement.

Two waves of wavelength 50 cm and 51 cm produced 12 beats per second. The velocity of sound is