The frictional force acting on a body at rest

Explanation

**Step-by-Step Solution:**

1. **Understanding Friction**: Friction is a force that opposes the relative motion between two surfaces in contact. It acts in the opposite direction to the applied force.

2. **Types of Friction**: There are two main types of friction:
- **Static Friction**: This is the frictional force that acts on a body at rest. It prevents the body from starting to move when a force is applied.
- **Kinetic Friction**: This is the frictional force acting on a body that is already in motion.

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