`3` moles of an ideal mono atomic gas performs a cycle as shown in fig. `If` gas temperature `T_(A)=400 K` `T_(B)=800K,T_(C)=2400K`, and `T_(D)=1200K`. Then total work done by gas is

Answer

20

Explanation

`"Process"_(1®2)` and `"Process"_(3®4)` are isochoric process.
`W_(12) = 0 , W_(34) = 0`
`W_(23) = nR (T_(3)-T_(2))`
`= 3R (2400 - 800) = 4800R`
`=3R =nRT (2400 - 800) = 4800R`
`W_(41) = nRT (T_(1)-T_(4))`
`= 3R (400 - 1200) =- 2400R`
`W = (4800 -2400) R =2400 R kJ`