Newton's Laws - Examples

A magician pulls a tablecloth out from under dishes and glasses on a table without disturbing them.

1st Law - The force did not act on the dishes and glasses, so they stay at rest.

A person not wearing a seat belt flies through a car window when someone slams on the brakes because the person's body wants to remain in continuous motion even when the car stops.

1st Law - The force did not act on the person so he just keeps on moving.

A person's body is thrown outward as a car rounds a curve on a highway.

1st Law - The force of the car stopping did not act on the person so he kept on moving.

A person is skateboarding, but hits a curb and flies forward, while the skateboard stays behind.

1st Law - The force only acted on the skateboard, so he stays in motion.

A student leaves a pencil on a desk and the pencil stays in the same spot until another student picked it up.

1st Law - There was no force acting on the pencil (until the other student picked it up) so it stayed at rest.

A picture is hanging on a wall and does not move.

1st Law - Things that are at rest tend to stay at rest, and there is not a force acting on it so it stays still.

Two students are in a baseball game. The first student hits a ball very hard and it has a greater acceleration than the second student who bunts the ball lightly.

2nd Law - A higher force equals a higher acceleration, so the ball that was hit with a greater force will accelerate more.

A child and an adult are going down a water slide with the same force of the water coming out. The child reaches the pool faster than the adult.

2nd Law - The adult has more mass than the child, so it will take more force on the adult to reach the child's acceleration.

Pushing a child on a swing is easier than pushing an adult on the same swing, because the adult has more inertia.

2nd Law - The more mass you have (inertia) the more force you need to push it at the same speed.

A soccer ball accelerates more than a bowling ball when thrown with the same force.

2nd Law - The soccer ball weighs less than the bowling ball, so you need less force to get it to have the same acceleration as the bowling ball.

Rockets are launched into space using jet propulsion where exhaust accelerates out from the rocket and it accelerates in the opposite direction.

3rd Law - The reaction force to the action force is in the opposite direction.

You sit in a chair and don't fall to the ground.

3rd Law - The reaction of you sitting in the chair is the chair pushing back on you.

A soccer player kicks a ball with their foot and their toes are left stinging.

3rd Law - The soccer ball pushed back on his foot, and that is the reaction force.