An iron ball at `40^@C` is dropped in a mug containing water at `40^@C` . The heat will

Options

A. flow from iron ball to water.
B. not flow from iron ball to water or from water to iron ball.
C. flow from water to iron ball.
D. increase the temperature of both.

Explanation

### Step-by-Step Solution:

1. **Understand the Scenario**: We have an iron ball at a temperature of 40°C and a mug of water also at a temperature of 40°C.

2. **Identify the Concept of Heat Transfer**: Heat transfer occurs when there is a temperature difference between two objects. Heat flows from the hotter object to the cooler object until thermal equilibrium is reached.

3. **Compare the Temperatures**: In this case, both the iron ball and the water are at the same temperature (40°C).

4. **Determine Heat Flow**: Since there is no temperature difference (both are at 40°C), there will be no heat transfer. Heat will not flow from the iron ball to the water, nor from the water to the iron ball.

5. **Conclusion**: Therefore, the heat will remain unchanged in both the iron ball and the water, and no heat will be transferred.

### Final Answer:
The heat will not be transferred between the iron ball and the water.

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