Q.

Reversible expansion of an ideal gas under isothermal and adiabatic conditions are as shown in the figure.        


AB→ Isothermal expansion
AC→ Adiabatic expansion
Which of the following options is not correct                                      [2019]

1 ΔSisothermal>ΔSadiabatic  
2 TA=TB  
3 Wisothermal>Wadiabatic  
4 TC>TA  

Ans.

(4)

For an ideal gas, internal energy is a function of temperature. Final temperature i.e., TC for adiabatic process is less than its initial temperature i.e., TA
∴  TC<TA