What is an example of inertia?

An example of inertia is when a person is sitting in a moving car and the car suddenly brakes. Due to the person's inertia, their body wants to keep moving forward even though the car has stopped. This can cause the person to lurch forward in their seat unless they are wearing a seatbelt to hold them in place.

Inertia is the tendency of an object to resist changes in its motion. The more mass an object has, the more inertia it has, meaning it will be harder to accelerate or decelerate. In this example, the person's body has inertia and wants to keep moving forward at the same speed as the car until an external force, in this case the brakes, act upon it.