Question

In places of hot climate, it is advised that the outer walls of houses be painted white. Explain.

Answer 1

Generally black color absorbs more heat when a huge amount of light falls on it. That is why our hair (which is black in color) absorbs more heat than the remaining body. Our hair absorbs more light and becomes warm.

Complete step by step solution:
- In the question it is given that in hot places it is advised to paint the walls of houses with white, why.
- Generally white color reflects all the wavelengths of light which are going to fall on it.
- If the white color reflects all the light containing different wavelengths then it will be having no energy within it.
- Means white color is not going to keep the surrounding heat within it.
- Black color absorbs more heat than the white color.
- That’s why in hot climates it is advised to paint the outer walls with white color due to less absorbance of heat by the white color.

Note: In summer the roofs of the several buildings in hot climate areas are coated with white color to make the house at low temperature. It is advised to coat the roofs of the buildings in hot climate areas in summer only. Roofs of the buildings in hot climate areas are not advised to coat with black color due to its high absorbance nature of all the wavelengths.