Method and Materials

 Analytic Essay

Backround Essay






Lab Report



Method and Materials




DEEP Homesite


- At least 8 balloons

- 1 pump or air compressor with a pressure gauge.

- A 25ft hose for the air compressor.

- A depth measuring device.

- 2 hose rings, if needed (this depends on the type of hose and air compressor attachments).

- Between 50 and 70 pounds of weight. (This weight should be attached to a belt or inside a bag. The belt or bag should be attached to a rope which can be tied to an object on the surface.)

- 1 balloon air filler (this a nozzle that is attached to the end of the hose)

- Over 30 feet of string for the weights.



Preparing the experiment

Assemble the pump or the air compressor and attach it to the hose. Attach the end of the air hose to the air nozzle of the pump with a hose ring if needed. Then attach the balloon air filler nozzle to the other end of the hose. Attach the balloon to the end of the air nozzle. Fill either the bag or belt with the weights, and tie your string to the device holding the weights. Prepare your depth measuring device to use for each individual trial.

Performing the experiment:
Have one member of the team dive to the bottom so that he can attach the balloon and hose to the weights. In addition, he can help to signal to the member at the top who is recording the information and the results of the experiment. He will also use the depth measuring device so he can find the appropriate depth at which to place the balloon. One member of the team will stay at the surface in order to operate the pump and moniter the air in the balloon. He will record the results for the different coordinates of depth and pressure at which the balloon bursts. He will tie the string attached to the weights to something on land so it will stay in place under water to weigh down the overly bouyant balloon.
The first portion of the experiment will be tested at sea level. With 14.7 psi, one atmosphere will be exerted upon the balloon. We will pump in a constant motion or turn on the air compressor so that it distributes a constant flow of air. As the pump distributes air, the man at the top will be constantly checking the air pressure gauge, waiting for the balloon to pop. Since there will be no issue with the bouyancy of the balloon, weghting will not be needed. This is perhaps the simplest trial, because everthing is above water. The various depths will be recorded in graph form, along with the pressure required to rupture a lung/balloon in a x/y, line graph format. Then this will be tested underwater, at increments of 5 feet. The balloon attached to the hose will be lowered by the diver to the desired depth. The diver under water will make one tug on the hose when the balloon is at the exact depth to signal to the person at the top to start filling the balloon. The member at the top will start to pump air into the balloon until it bursts and the member underwater gives the signal to stop the pump and check the pressure at which it popped. The member at the top will then record the presssure at which the balloon popped for the depth it was tested under. Continue this method until you have gone down to 15 feet. Analyze your results and turn them into graph form if needed.





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