What is the principle of evaporation Class 7?

It looks like you're looking at evaporation, which is a classic topic in Class 7 Science!

Here is a quick, structured breakdown of what evaporation is and the key factors that affect it, just in case you're studying for an exam or completing an assignment:

What is Evaporation?

• Definition: The process where a liquid turns into a gas at temperatures below its boiling point.

• Where it happens: It occurs only at the surface of the liquid.

• How it works: Molecules at the surface constantly collide and gain energy. The ones with the highest kinetic energy break free from the liquid's surface and escape into the air as vapor.

Factors affecting the rate of evaporation

1. Surface Area: A larger surface area (like spreading wet clothes out) increases the rate of evaporation because more molecules are exposed to the air.

2. Temperature: Higher temperatures give molecules more kinetic energy, making them escape faster.

3. Humidity: Lower humidity (dry air) speeds up evaporation because the air can hold more water vapor.

4. Wind Speed: Moving air blows away water molecules just as they escape, preventing the surrounding air from becoming saturated.