Question

Heat given to a system is 35 joules and work done by the system is 15 joules. The change
in the internal energy of the system will be
-P)
a:
(A) - 50 J
TE
(B) 20 J
(C) 30 j
(D) 50 J​

Answer 1

Answer: (B) 20 J

Explanation: This is because heat given is energy absorbed i.e. 35 J

Work done is expenditure of that energy into the surroundings i.e. 15 J

Hence the change in internal energy = 35 - 15 = 20 J