One calorie is equal to ______.

Options

A. 0.4184 Joule
B. 4.184 Joule
C. 41.84 Joule
D. 418.4 Joule

Answer

To solve the question "One calorie is equal to ______," we need to determine the relationship between calories and joules, which are both units of energy.

### Step-by-Step Solution:

1. **Understanding the Definition of Calorie**:
- A calorie is defined as the amount of energy required to raise the temperature of 1 gram of water by 1 degree Celsius.

2. **Conversion Factor**:
- It is known that 1 calorie is equivalent to a specific amount of joules. The standard conversion factor is:
\[ 1 \text{ calorie} = 4.184 \text{ joules} \]

3. **Conclusion**:
- Therefore, we can conclude that:
\[ \text{One calorie is equal to } 4.184 \text{ joules.} \]

### Final Answer:
One calorie is equal to **4.184 joules**.

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