How can charging take place when the substances are rubbed?

Explanation

### Step-by-Step Solution

1. **Understanding Neutral Bodies**: Initially, both substances (let's call them Body A and Body B) are neutral. This means they have an equal number of protons (positively charged) and electrons (negatively charged).

2. **Rubbing the Substances**: When Body A and Body B are rubbed against each other, a process called charging by friction occurs. This friction causes some electrons to move from one body to the other.

3. **Electron Transfer**: During the rubbing process, electrons from Body A may transfer to Body B. This movement of electrons is due to the frictional force between the two bodies.

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