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An engine takes in 5 moles of air at 20 ° C and 1 atm , and compresses it adiabatically to 1 / 10 th of the original volume. Assuming air to be a diatomic ideal gas made up of rigid molecules, the change in its internal energy during this process comes out to be XkJ . The value of X to the nearest integer is:

Correct answer

0

Step-by-step solution

T 1 V 1 γ - 1 = T 2 V 2 γ - 1 T 2 = T 1 V 1 V 2 γ - 1 = T 1 ( 10 ) 7 5 - 1 T 2 = T 1 ( 10 ) 2 / 5 Δ V = 5 2 n R ; 5 2 × 5 × 3 10 2 / 5 - 1 ( 293 ) 625 6 × 1 . 5 × 293 = 461440 ≈ 46 ks

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