In chulhas, gaps are left between the logs

Options

A. to decrease the ignition temperature of the fuel
B. to allow the air to enter and facilitate fuel burning
C. to cut off the supply of air
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks why gaps are left between the logs in chulhas (traditional stoves).

2. **Analyzing the Options:**
- Option 1: Decrease the ignition temperature of fuel.
- Option 2: Allow the air to enter and facilitate fuel burning.
- Option 3: Cut off the supply of air.
- Option 4: All of these.

3. **Identifying the Purpose of Gaps:**
The primary purpose of leaving gaps between the logs is to allow air to enter. Air (specifically oxygen) is essential for combustion, which is the process of burning fuel.

4. **Evaluating Each Option:**
- Option 1 is incorrect because the gaps do not decrease the ignition temperature; they help with combustion.
- Option 2 is correct as the gaps allow air to enter, which facilitates burning.
- Option 3 is incorrect because cutting off the air supply would hinder combustion.
- Option 4 is incorrect since not all options are correct.

5. **Conclusion:**
The correct answer is Option 2: to allow the air to enter and facilitate fuel burning.

**Final Answer:**
The gaps left between the logs in chulhas are primarily to allow air to enter and facilitate fuel burning (Option 2).

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