If sink and source temperature of a refrigerator are `4^(@)C and 15^(@)C` respectively. Then efficiency of refrigerator is:

Options

A. 0.076
B. 0.0382
C. 0.019
D. 1

Explanation

To find the efficiency of the refrigerator given the sink and source temperatures, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the temperatures**:
- Sink temperature (T) = 4°C
- Source temperature (T') = 15°C

2. **Convert temperatures from Celsius to Kelvin**:
- To convert Celsius to Kelvin, we add 273 to the Celsius temperature.
- Sink temperature in Kelvin (T) = 4 + 273 = 277 K
- Source temperature in Kelvin (T') = 15 + 273 = 288 K

3. **Use the formula for the efficiency of the refrigerator**:
- The efficiency (η) of a refrigerator is given by the formula:
\[ \eta = 1 - \frac{T}{T'} \]
- Here, T is the sink temperature in Kelvin, and T' is the source temperature in Kelvin.

4. **Substitute the values into the formula**:
- Substitute T = 277 K and T' = 288 K into the efficiency formula:
\[ \eta = 1 - \frac{277}{288} \]

5. **Calculate the efficiency**:
- First, calculate the fraction:
\[ \frac{277}{288} \approx 0.9646 \]
- Now, subtract this from 1:
\[ \eta = 1 - 0.9646 \approx 0.0354 \]

6. **Final result**:
- The efficiency of the refrigerator is approximately 0.0354 or 3.54%.