One mole of an ideal monatomic gas undergoes a process described by the equation PV³ = constant. The heat capacity of the gas during this process is

A rectangular film of liquid is extended from (4 cm $$ \times $$ 2 cm) to (5 cm $$ \times $$ 4 cm). If the work done is 3 $$ \times $$ 10^$$-$$4 J, the value of the surface tension of the liquid is

Three sound waves of equal amplitudes have frequencies (n $$-$$ 1), n, (n + 1). They superimpose to give beats. The number of beats produced per second will be

A body of mass m is attached to the lower end of a spring whose upper end is fixed. The spring has negligible mass. When the mass m is slightly pulled down and released, it oscillates with a time period of 3s. When the mass m is increased by 1 kg, the time period of oscillations becomes 5 s. The value of m in kg is