Here's why:
* Newton's First Law: 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.
* Constant Velocity: This means the object is not accelerating.
* Balanced Forces: For an object to have constant velocity, the forces acting on it must be balanced. This means the force pulling the object must be equal and opposite to the force opposing its motion (friction).
In simpler terms: If you pull a box across the floor at a steady pace, you're applying a force that's exactly counteracting the friction between the box and the floor.