Name the S.I. unit of heat. How is it related to the unit calorie?

Answer

**Step-by-Step Solution:**

1. **Identify the SI Unit of Heat:**
The SI unit of heat is Joule. It is denoted by the symbol 'J'.

2. **Understanding the Relationship Between Joules and Calories:**
To understand how Joules relate to calories, we need to know the conversion factor between these two units.

3. **Conversion Factor:**
The relationship can be expressed as:
\[ 1 \text{ Joule} \approx 0.24 \text{ calories} \]
This means that one Joule is approximately equal to 0.24 calories.

4. **Inverse Relationship:**
To find out how many Joules are in one calorie, we can take the reciprocal of the above relationship:
\[ 1 \text{ calorie} \approx \frac{1}{0.24} \text{ Joules} \approx 4.17 \text{ Joules} \]
Thus, one calorie is approximately equal to 4.17 Joules.

5. **Conclusion:**
The SI unit of heat is Joule, and it is related to the calorie such that 1 Joule is approximately 0.24 calories, and conversely, 1 calorie is approximately 4.17 Joules.

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