Here's a really cool rocket model that you can build at home.
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This is what you'll need:
1. An empty plastic soda bottle
2. A cork that will fit snugly into the soda bottle
3. A bicycle pump
4. an inflating needle (the kind used to inflate basketballs and
footballs.)
5. some cardboard
6. some tape
7. A nail |
First, we need to cut the card board into fins for the rocket (you'll
need four of them). Attach your fins to the bottle. Then, have a
grown up help you with this one, take the nail and make a hole in it
big enough so that the inflating needle fits snugly in the hole. Next
we need to fill the bottle with water one quarter of the way up
(you'll want to do this over a sink and use a funnel while you're at
it). Then place the cork snugly into the mouth of the soda bottle.
Attach the pump to the inflating needle.
Now, this part is important, you need to take the water bottle rocket outside!!
Once we're outside we place the rocket on it's fins and the pump on the
ground, making sure not to stand over the rocket. Then start
pumping!! This causes the air pressure inside the bottle to build up.
Pretty soon the cork can't hold the air pressure any more, and the
water and the air rush out of the neck of the bottle just like gas
rushing out of the nozzle of a rocket. Rocket's work because of
Newton's 3rd law of motion: for every action there is a reaction. The
action part is the air and water rushing out of the bottle. The reaction
the rocket being pushed in the opposite direction.
