The efficiency of a Canot engine working between `800K` and `500K` is

Options

A. 0.4
B. 0.625
C. 0.375
D. 0.5

Explanation

To find the efficiency of a Carnot engine working between two temperatures, we can use the formula for efficiency:

\[ \text{Efficiency} = 1 - \frac{T_2}{T_1} \]

Where:
- \( T_1 \) is the higher temperature (in Kelvin)
- \( T_2 \) is the lower temperature (in Kelvin)

### Step-by-Step Solution:

1. **Identify the temperatures**:
- The higher temperature \( T_1 = 800 \, K \)
- The lower temperature \( T_2 = 500 \, K \)

2. **Substitute the values into the efficiency formula**:
\[ \text{Efficiency} = 1 - \frac{T_2}{T_1} = 1 - \frac{500}{800} \]

3. **Calculate the fraction**:
\[ \frac{500}{800} = 0.625 \]

4. **Subtract from 1**:
\[ \text{Efficiency} = 1 - 0.625 = 0.375 \]

5. **Convert to percentage (if needed)**:
\[ \text{Efficiency} = 0.375 \times 100 = 37.5\% \]

Thus, the efficiency of the Carnot engine working between 800 K and 500 K is **0.375** or **37.5%**.