Newton's Laws of Motion

Motion, any one who has kids know all about motion.  It seems like they are always in motion.  But what do scientist say motion is? They say motion is a change in position, and you use force to change position.  And what is force? Well, force is something that get's things moving like a push, pull or throw.  But force can also make things stop too, like gravity or friction.

This meeting we did many experiments that demonstrated what each of Newtons 3 laws were.

First, on a piece of paper or a large wipe erase board I wrote out Newton's First Law of Motion.
First Law of Motion- If no force acts on an object at rest it will remain at rest.  If an object is moving, it will continue moving at the same speed and in the same direction if no forces act on it.

Experiment 1-  The Flick

Needed-mugs or heavy cups, playing card, coins

1. I personally gave each child a cup, this needs to be something that will not break easy. Then gave them a card and a coin.  I put extra cards and coins in the middle.
2. Have the children put a card on top of the cup and a coin on top of the card.
3. Show them how to flick the card and see what happens to the coin?  The coin will fall into the cup. Remind them that an object at rest will stay at rest until acted upon.  The coin resist moving, while the card moved because you apply a force.
4. Let the children experiment.  I found that they enjoyed adding several cards and several coins.  They just enjoyed experimenting.
There is a video of this- the flick

Experiment 2

Needed- piece of paper for each child, cup (does not break easily)

1. Give the children a cup and a piece of paper, and have them place the cup on the edge of the paper.
2.  In a quick motion pull the paper out from under the glass.  When they pull the paper the cup should stay put.
Again, the cup resists the movement, the paper moves because it is pulled.

Experiment 3   Friction and Gravity

Needed- Car, smooth surface like table and rough surface (I used a towel)
1. Put a car in the middle of the table and ask them if it is moving? Of course not. It is not moving because there is no FORCE  being applied to it. An object will stay at rest until a force is applied to it.  Ask them how they think they could make it move?
2. Push the car on the smooth surface, like table. Talk to the children about how it  the car glides across the table.  Ask them what they think is going on.  Tell them that there is very little friction slowing the car down. If there were not little bumps in the table that they could not see, the car would go on and on.  Remind them that a object in motion will stay in motion until some force slows it down and this force on the table is friction.
3. Roll the table over a rough surface (carpet or towel) and have them notice how it stops quickly.  That is because friction is slowing the car down.
4. Now throw the car up into the air?  What happens?  The car will move up, but then it moves down.  Ask them why?  It is of course coming down because of gravity.  Gravity is a force.  If you can, let them experiment with it and keep using the word "gravity", especially if your kids are young.
5. Oh another possibility is you can use is have the car slam into something. An arm, body, something.  It will stop because it crashed.

Newtons 2nd Law of Motion is that the amount of force needed to produce a given change in the motion of an object depends on the mass of the object.

Experiment 1
tore up paper or blown up balloon, car, rock (or solid object)
1.  Have the kids blow on paper or blown up balloons and see how very little force it takes to move them.
2. Have them blow on a toy car, and see how much force it takes to move a toy car.  A little more, but it is possible.
3. Have them blow on a solid object like a bigger rock, and your breath will not move it.

f = ma  or force = mass times acceleration. is the equation.  For older kids you could choose to go over this but younger kids it is probably to much.

Experiment 2

1  We moved over to the couch.. I tried to blow and blow on it but it would not move!  I let the other kids blow on the couch but they could not move the couch.  Our blows were just not enough to move the big couch.
2.  Then I had the smallest kid move the couch and the smallest kid could not.  We worked up through the biggest kids until finally someone could move the couch.  In our home it was me.  I was the only one able to provide enough force to move the mass.
3. EXTRA  I had the kids hide in the hall and move some magazines under each foot and asked them again to move the couch!  They just did not think that they could, so I asked the smallest kid to try again and guess what !!!  The smallest kid could.  I asked the kids to investigate why.  Well they saw the magazines and I explained that because the magazines LESSENED the friction, they were able to move the couch!

Newtons 3rd Law of Motion is that for every action there is an equal or apposite reaction.

Experiment 1
string, 2 straw, balloon, tape, ping pong ball (optional experiment) chairs, clothes pin

1. Blow up a balloon and clip it with the clothes line pin and tape it to a straw.  After you tape the balloon to the straw then put the string through the straw.
2. Tie the string to 2 chairs, pull the chairs as far apart as possible and pull the straw to one end of the string.
3. Release the pin and watch the air expel out of the balloon and push it forward.  For every action, the air being released from the balloon, there is a reaction, the balloon pushing forward.
Extra  Now put a ping pong ball on a straw.  Put the balloon/straw and the ping pong ball/ straw in the middle of the string and release the blown up balloon.  As the air from the balloon pushes out and pushing the balloon forward it pushes on the ping pong ball and forces it to move the other way.

Experiment 2
Needed- Springs from pens

1.  I took the springs out of pens, one for each child.
2. have the children try to force down the spring between 2 fingers.  As they are pushing down, can they feel the spring pushing back on their fingers.  For every action, which is pushing down on the spring, there is a reaction, the spring is pushing back.

Experiment 3
ball, smooth surface and skate board
1. Have the children stand on the skateboard and throw a ball.
What happens?  As they throw the ball forward, they are pushed backwards on the skateboard.  For every action, throwing a ball forward, causes a reaction, the skateboard moves you backwards.

Bill Nye has a great video on motion that you could watch

https://www.youtube.com/watch?v=ynyOm5SkeGE

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