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

Explanation

### Step-by-Step Solution:

1. **Understanding Color and Heat Absorption:**
- Different colors absorb and reflect light differently. Dark colors, like black, absorb most of the light and heat, while light colors, like white, reflect most of the light and heat.

2. **Properties of Black and White Surfaces:**
- A black surface is known as a "black body," which means it absorbs nearly all the light that hits it. This leads to an increase in temperature as it absorbs heat from sunlight.
- In contrast, a white surface reflects more than 90% of the incident light, which means it does not absorb much heat.
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