An ideal gas goes from state A to state B via three different

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An ideal gas goes from state A to state B via three different processes as indicated in the P-V diagram :

If Q₁ , Q₂ , Q₃ indicate the heat a absorbed by the gas along the three processes and ∆U₁ , ∆U₂ , ∆U₃ indicate the change in internal energy along the three processes respectively, then

1. Q₁ > Q₂ > Q₃ and ∆U₁ = ∆U₂ = ∆U₃
2. Q₃ > Q₂ > Q₁ and ∆U₁ = ∆U₂ = ∆U₃
3. Q₁ = Q₂ = Q₃ and ∆U₁ > ∆U₂ > ∆U₃
4. Q₃ > Q₂ > Q₁ and ∆U₁ > ∆U₂ > ∆U₃

Correct Option: A

Initial and final condition is same for all process
∆U₁ = ∆U₂ = ∆U₃
from first law of thermodynamics ∆Q = ∆U + ∆W
Work done ∆W₁ > ∆W₂ > ∆W₃ (Area of P.V. graph)
So ∆Q₁ > ∆Q₂ > ∆Q₃