The temperature of water at the bottom of a large waterfall is higher than that of the water at the top, because

Options

A. the falling water absorbs heat from the sun
B. the KE of the falling water is converted into heat
C. the water at the bottom has greater PE
D. rocks on the bed of the river give out heat

Answer

**Step-by-Step Solution:**

1. **Understanding the Scenario**: We have a large waterfall where water falls from a height. The question asks why the temperature of the water at the bottom is higher than that at the top.

2. **Considering Energy Forms**: As the water falls, it possesses potential energy due to its height. When it falls, this potential energy is converted into kinetic energy.

3. **Friction and Heat Generation**: When the water reaches the bottom, it interacts with the riverbed and the surrounding environment. The kinetic energy of the falling water is converted into heat energy due to friction between the water and the ground.

4. **Conclusion**: The increase in temperature at the bottom of the waterfall is primarily due to the conversion of kinetic energy into heat energy as the water falls and interacts with the surface.

5. **Final Answer**: Therefore, the correct explanation for the higher temperature of water at the bottom of the waterfall compared to the top is that the kinetic energy of the falling water is converted into heat (Option 2).

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