Stomp RocketsInstructions:

1. Set up the launch pad.

2. Place the rocket on the launcher.

3. Stomp on the launch pad.

How do they work?

• When you stomp on the launch pad, you increase pressure in the pad, which forces air into the rocket.

• Because the pad is really big and the tube to the rocket is really small, the air rushes into the rocket really quickly.

• Once the air enters the rocket it hits the top of the rocket, pushing it up into the air..

• Normal rockets carry their fuel with them and can let it out during the flight. The energy required to shoot off the stomp rocket comes all at the very beginning of the flight.

Air

Some things to try:

• Step on the launcher slowly.

• Step on the launcher quickly.

• Jump into the air and land on the launcher.

• Can you explain why sometimes the rocket goes higher?

• Can small kids make the rocket go as high as big kids?

The Motion of Flight• Not only planes can fly! Anything that moves

through the air is considered to be in flight, like baseballs and stomp rockets.

• There are certain rules that objects must obey while they are flying, like the force of gravity.

• Because these rules are always the same, we can predict how something will fly.

• In order to make the object go further, we can either change how hard we throw it or at what angle we throw it.

• From this graph, how would you throw a ball to make it go the furthest?

Stomp Rockets• According to Pascal’s Principle, pressure is

transmitted undiminished in a static fluid.• Hydraulic lifts work this way; the pressure

stays constant, so a small applied force over a small area translates to a large force over a large area

• In order to conserve energy, the small force must be applied over a large distance and creates the large force over a small distance.

• In order for our rocket to work, we observe the following:

– We can apply a large force by stomping on a pad with a large surface area

– The air needs to be able to travel up the length of the rocket (a greater distance than the top of the pad needs to travel)

– The force at the other end does not need to be as large because the rocket is light.

• Therefore, the stomp rocket acts like a hydraulic press in reverse.

Can I Fly a Stomp Rocket into Space?

•Whenever we are on earth’s surface there is a certain amount of energy keeping us there.

•If we want to leave earth’s gravity we have to have an energy that is just as big to push us there.

•For earth, in order to have this much energy we need to travel at 11,200 kilometers per second, or about 25,000 miles per hour!

•In order to match this energy, 99 elephants would have to jump off the Eiffel Tower!