What happens when a glass rod is rubbed with a silk cloth?

Options

A. It gains electrons.
B. It loses electrons.
C. It gains protons.
D. It loses protons.

Answer

### Step-by-Step Solution:

1. **Understanding the Materials**: We start with a glass rod and a silk cloth. Both materials have different properties when it comes to electrical charges.

2. **Friction and Charge Transfer**: When the glass rod is rubbed with the silk cloth, friction occurs between the two surfaces. This friction is crucial as it facilitates the movement of electrons.

3. **Movement of Electrons**: In this process, electrons from the glass rod are transferred to the silk cloth. This means that the glass rod loses some of its electrons.

4. **Resulting Charges**:
- Since the glass rod loses electrons, it becomes positively charged because it has more positive charges (protons) than negative charges (electrons).
- Conversely, the silk cloth gains those electrons, making it negatively charged.

5. **Conclusion**: Therefore, the glass rod loses electrons when rubbed with a silk cloth, resulting in a positive charge on the rod.

### Final Answer:
When a glass rod is rubbed with a silk cloth, it loses electrons and becomes positively charged.

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