Question

For a cyclic thermodynamic process

• A. \(Q=-W\) and \(\Delta U\neq 0\)
• B. \(Q=0\) and \(\Delta U=0\)
• C. \(Q\neq 0,\Delta U\neq 0\)
• D. \(Q=W\) and \(\Delta U=0\)

Hint:

Internal energy is a state function, so its change over a complete cycle is zero.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept
In a cyclic process the system returns to its initial state. Internal energy is a state function, so \(\Delta U=0\) over the cycle.

Step 2: Apply the first law
\(Q=\Delta U+W\) gives \(Q=W\) when \(\Delta U=0\). The net heat absorbed equals the net work done.

Step 3: Compare the options
Only \(Q=W\) and \(\Delta U=0\) fits.

Final Answer:
For a cyclic process Q equals W and the change in internal energy is zero. \[ \boxed{\text{(D) }Q=W\text{ and }\Delta U=0} \]