People use a variety of methods to wash clothes. Usually after adding the soap, they ‘beat’ the clothes on a stone, or beat it with a paddle, scrub with a brush or the mixture is agitated in a washing machine. Why is agitation necessary to get clean clothes?

Explanation

To understand why agitation is necessary to get clean clothes, let's break down the process step by step:

### Step 1: Understanding the Role of Soap and Detergent
- Soap and detergents are surfactants that help to remove dirt and grease from clothes. They work by reducing the surface tension of water, allowing it to spread and penetrate fabrics more easily.

### Step 2: The Process of Cleaning
- When soap or detergent is added to water, it forms micelles. These micelles encapsulate dirt and grease, which are often hydrophobic (water-repelling) substances.

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