Assertion (A): Steam is more harmful for human body than the boiling water in case of burn.
Reason (R): Boiling water contains more heat than steam.

Explanation:
When it comes to burns, both steam and boiling water can cause damage to the human body. However, the assertion states that steam is more harmful than boiling water, while the reason provided is that boiling water contains more heat than steam. Let's evaluate the validity of these statements.

Understanding Steam and Boiling Water:
- Steam: Steam is the gaseous form of water that is formed when water reaches its boiling point and evaporates. It is invisible and consists of tiny water droplets suspended in the air.
- Boiling Water: Boiling water is water that has reached its boiling point and is in the liquid state.

Evaluating the Assertion (A):
The assertion states that steam is more harmful for the human body than boiling water in case of a burn. This statement is true, and here's why:
- Steam carries more heat energy compared to boiling water. When water evaporates and turns into steam, it absorbs a significant amount of heat energy from its surroundings. This energy is released when steam comes into contact with a cooler surface, such as the human body. As a result, steam causes more severe burns than boiling water.
- Steam has a higher heat transfer capacity than boiling water. Steam can transfer heat more rapidly to the skin due to its gaseous nature. It can penetrate the skin more easily and cause deeper burns compared to boiling water.

Evaluating the Reason (R):
The reason provided states that boiling water contains more heat than steam. This statement is false, and here's why:
- Heat is a measure of the total energy contained in a substance. When water reaches its boiling point and turns into steam, it absorbs additional heat energy from its surroundings. This means that steam actually contains more heat energy compared to boiling water.
- The reason fails to explain why steam is more harmful for the human body than boiling water. While it is true that boiling water contains heat, it does not address the fact that steam can transfer heat more rapidly and cause more severe burns.

Conclusion:
In conclusion, the assertion (A) is true because steam is indeed more harmful for the human body than boiling water in case of a burn. However, the reason (R) is false because boiling water does not contain more heat than steam. The severity of a burn caused by steam is primarily due to its higher heat transfer capacity and ability to penetrate the skin more easily.