In a reversible adiabatic change `Delta Q` is

Options

A. infinity
B. zero
C. equal to `C_v dt`
D. equal to `nRln V_2//V_1`

Answer

To solve the question regarding the change in heat (ΔQ) in a reversible adiabatic process, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms:**
- **Reversible Process:** A reversible process is one that can be reversed without leaving any trace on the surroundings. In such processes, the system is always in thermodynamic equilibrium.
- **Adiabatic Process:** An adiabatic process is one in which no heat is exchanged with the surroundings. This means that the system is insulated, and there is no heat transfer (ΔQ = 0).

2. **Identify ΔQ in an Adiabatic Process:**
- In an adiabatic process, by definition, the change in heat (ΔQ) is zero. This is because the system does not gain or lose heat to the surroundings.

3. **Conclusion:**
- Since ΔQ represents the change in heat and we have established that in an adiabatic process ΔQ = 0, we conclude that:
\[ \Delta Q = 0 \]

4. **Select the Correct Option:**
- Given the options provided in the question, the correct answer is **0**.