A gas expands against a variable pressure given by `P = (20)/(V)` (where P in atm and V in L). During expansion from volume of 1 litre to 10 litre, the gas undergoes a change in internal energy of 400 J. How much heat in J is absorbed by the gas during expansion? [1 L atm =

Answer

5

Explanation

`Delta W=underset(1)overset(-10)intPdv= -20underset(1)overset(10)int(dv)/(V)=20[ l n(V)]_(1)^(10)= -20 ln(10)= -4605 J`
`Delta q=Delta U-Delta w`
`= 400-(-4605)=5005 J ~~ 5 KJ`