In hot water bottles, water is used because

Options

A. its specific heat is low
B. its specific heat is high
C. it is cheap
D. it is easily available

Answer

**Step-by-Step Solution:**

1. **Understanding the Purpose of Hot Water Bottles:**
- Hot water bottles are used to provide warmth and relief from pain or discomfort. They are often used for therapeutic purposes, such as alleviating muscle pain or menstrual cramps.

2. **Identifying the Properties of Water:**
- Water is chosen for hot water bottles due to several properties, including its availability, cost-effectiveness, and specific heat capacity.

3. **Specific Heat Capacity:**
- Specific heat capacity is defined as the amount of heat required to raise the temperature of a unit mass of a substance by 1 degree Celsius.
- Water has a high specific heat capacity, which means it can absorb a lot of heat without a significant increase in temperature.

4. **Implications of High Specific Heat Capacity:**
- Because of its high specific heat capacity, water can store a large amount of heat energy. This allows hot water bottles to remain warm for an extended period, providing consistent warmth to the user.

5. **Conclusion:**
- Therefore, water is used in hot water bottles primarily because it has a high specific heat capacity, which allows it to store and retain heat effectively, making it suitable for therapeutic applications.

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