Question

An adiabatic process is one in which :

• A. the temperature of the gas changes
• B. the change in internal energy is equal to the mechanical work done
• C. no heat enters or leaves the gas
• D. all of the above

Answer 1

The correct option is B the change in internal energy is equal to the mechanical work done

In thermodynamics, an adiabatic process is one that occurs without transfer of heat or matter between a thermodynamic system and its surroundings.

For a closed system, one may write the first law of thermodynamics thus:

$\Delta U=Q–W$

Where,

$\Delta U$ denotes the change of the system's internal energy,

$Q$ the quantity of energy added to it as heat, and

W the work done on it by its surroundings.

If the system walls are adiabatic (Q = 0), but not rigid (W ≠ 0), then change in internal energy is equal to change in internal energy.