Discussion Forum

1)

When a system is taken from state i to state f along the path iaf, it is found that Q = 50 cal and W = 20 cal. Along the path ibf Q = 36 cal W along the Path ibf is

Answer:

Option B

Explanation:

For path iaf, Q = 50 cal W = 20 cal

By the first law of thermodynamics,

ΔU = Q - W = 50 - 20 = 30 cal.

For path ibf

Q' = 36 cal

W' =?

Or, W' = Q' - ΔU'

Since the change in internal energy does not depend on the path,

therefore ΔU' = 30cal

.'. W' = Q' - ΔU' = 36 - 30 = 6 cal.