When the temperature difference between inside and outside of a room is `20^(@)C`,the rate of heat flow through a window is `273 Js^(-1)`. If the temperature difference becomes 20K, the rate of flow of heat through the same window will be:

Options

A. `253 Js^(-1)`
B. `273 Js^(-1)`
C. `293 Js^(-1)`
D. Given by one of the above mentioned values

Explanation

To solve the problem, we need to understand the relationship between the temperature difference and the rate of heat flow. The key point here is that the temperature difference (ΔT) can be expressed in either Celsius or Kelvin, and the rate of heat flow will remain the same as long as the numerical value of the temperature difference is the same.

### Step-by-Step Solution:

1. **Identify the Given Values**:
- Initial temperature difference (ΔT) = 20°C
- Rate of heat flow (dQ/dt) = 273 J/s

2. **Understand Temperature Difference in Celsius and Kelvin**:
- The temperature difference of 20°C is equivalent to a temperature difference of 20K.
- This is because the difference in temperature is the same in both scales. The Celsius scale is offset by 273 from the Kelvin scale, but the difference remains unchanged.

3. **Apply the Concept**:
- Since the rate of heat flow is directly proportional to the temperature difference, if the temperature difference remains the same (20°C = 20K), the rate of heat flow will also remain the same.

4. **Conclusion**:
- Therefore, when the temperature difference becomes 20K, the rate of heat flow through the same window will still be 273 J/s.

### Final Answer:
The rate of heat flow through the window when the temperature difference is 20K will be **273 J/s**.

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