Newton's First Law of Motion states that an object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Friction is a force that directly contradicts this law. Here's how:

* Friction Opposes Motion: Friction acts in the opposite direction of motion. This means it always tries to slow down or stop an object that is moving.

* Friction as an Unbalanced Force: When friction acts on an object, it becomes an unbalanced force, as it is the only force acting against the object's motion. This unbalanced force then causes the object to slow down or stop, contradicting Newton's First Law.

Example:

Imagine a book sliding across a table. The book is in motion, but friction between the book and the table acts as an unbalanced force, slowing it down until it eventually comes to a stop.

Without Friction:

If there was no friction, the book would continue to slide across the table forever, as per Newton's First Law. This is because no unbalanced force would be acting on it to change its state of motion.

In Conclusion:

Friction directly affects Newton's First Law of Motion by introducing an unbalanced force that opposes the motion of an object. This force causes objects to slow down and eventually stop, despite their initial state of motion.