SECOND & THIRD LAW OF MOTION

             SECOND LAW OF MOTION
 When a force acts on something , it makes it accelerate (go faster,slower, or change direction).The amount of acceleration depends on the size of the force and the mass of the object .The bigger the force or the lighter the object ,the more it accelerates.

 SMALL MASS, SMALL FORCE

 Kick a ball lightly(with a small force)and it accelerates at a steady rate.The acceleration is equal to the size, of the force divided by the mass of the ball.

 SMALL MASS, MEDIUM FORCE

 Kick the small ball with twice the force ,and you get twice the acceleration . If it flies in a straight line .It accelerates to twice the speed in the same time.

DOUBLE MASS, LARGE FORCE

A heavier ball needs a bigger force to get it moving ,If you use eight times your original force and the ball is twice as heavy , you get four time the original acceleration.

FORCE=MASS*ACCELERATION

     THIRD LAW OF MOTION

 Newton,s third law says that  when a force act on something,there is always another force just  a big acting in the opposite direction.
If the original force is called  ACTION .  The opposite force is called  REACTION. That's why the third law is often written in a shortened form every action has equal and opposite reaction.

 ACTION

Imagine you're on a skate board and you push against a wall(action).The wall push back wit a reaction force causing you to roll away from the wall.

 REACTION

If you push a friend , who is also on a skateboard your force(action) moves them away from you.The reaction force makes you moves in the opposite direction at the same speed as your friend.