Thermodynamics: RE-NEET 2026

Hard· Thermodynamic Processes (Isothermal Process)· +4 / −1

Consider the reversible processes for

1.0

mol of an ideal gas as shown in the figure. Figure: a

P

V

cycle with four reversible steps: process

1

is an isothermal expansion at

T_1

from

(p_1, V_1)

(p_2, V_2)

; process

2

is an adiabatic expansion from

(p_2, V_2, T_1)

(p_3, V_3, T_2)

; process

3

is an isothermal compression at

T_2

from

(p_3, V_3)

(p_4, V_4)

; process

4

is an adiabatic compression from

(p_4, V_4, T_2)

back to

(p_1, V_1, T_1)

. Processes

2

and

4

are adiabatic. Question diagram

w_1

w_2

w_3

and

w_4

represent work done (in calories) in the processes 1, 2, 3 and 4, respectively;

\Delta U_2

and

\Delta U_4

are changes in the internal energy for the processes 2 and 4, respectively. [use

R = 2\ \mathrm{cal\,K^{-1}\,mol^{-1}}

] The correct option is

Related questions