Light

Inertia

Definition

Inertia is the tendency of an object to resist changes in its motion. It refers to the property of matter that causes objects to stay at rest or continue moving in a straight line at a constant velocity unless acted upon by an external force.

Analogy

Imagine you're sitting on a skateboard and someone pushes you from behind. If you have a lot of inertia, it will be harder for the person to change your speed or direction. You'll keep rolling forward until another force, like friction or hitting something, stops you.

Related terms

Mass: Mass is the measure of the amount of matter in an object. It determines how much inertia an object has.

Newton's First Law: Also known as the law of inertia, it states that an object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and direction unless acted upon by an external force.

Momentum: Momentum is a property of moving objects and depends on both mass and velocity. It describes how difficult it is to stop or change the motion of an object.