Due to surface tension, the excess pressure inside a smaller drop is $9$ units. If $27$ smaller drops combine then excess pressure inside the bigger drop is

A body cools in $7$ minutes from $60^\circ$C to $40^\circ$C. What time (in minutes) does it take to cool from $40^\circ$C to $28^\circ$C, if its surrounding temperature is $10^\circ$C ? (Newton's law of cooling holds good)

A rigid diatomic gas undergoes adiabatic change. Its pressure P and temperature T are related as $P \propto T^x$ where x is

If $\Delta Q$ is the amount of heat supplied to 'n' moles of a rigid diatomic gas at constant pressure, $\Delta U$ is the change in internal energy and $\Delta W$ is the work done then $\Delta W : \Delta U : \Delta Q$ is