Friction is a self adjusting force.

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 direction opposite to that of the applied force.

2. **Self-Adjusting Nature of Friction**: The statement "friction is a self-adjusting force" means that the force of friction changes in response to the applied force. It adjusts itself to prevent motion until a certain limit is reached.

3. **Example of Friction**: Consider an object resting on a rough surface. If we apply a force of 1 Newton to the left, the frictional force will also act to the right with an equal magnitude of 1 Newton, keeping the object in equilibrium.

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