Frame of reference facts

Two reference frames
Two cars moving at different but constant velocities observed from stationary inertial frame S attached to the road and moving inertial frame S′ attached to the first car.

A frame of reference is how one knows if an object is moving. For example, when you see a ball roll down a street, you can tell the ball is moving because the frame of reference is the streets, whatever may be on the side of the roads or the Earth. All of these are a frame of reference.

The most common frame of reference is Earth itself, even though it moves.

Images


Frame of reference Facts for Kids. Kiddle Encyclopedia.