Friction depends on the _________ of surfaces.

Explanation

To answer the question "Friction depends on the _________ of surfaces," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Friction**: Friction is a force that opposes the relative motion between two surfaces in contact. It arises when one surface moves or attempts to move over another surface.

2. **Identifying Factors Affecting Friction**: The amount of friction that occurs between two surfaces depends on several factors, primarily the nature of the surfaces in contact.

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