I performed an experiment, using a Vernier projectile launcher, in order to see how far a metal ball can be shot, to be specific, to what extent changing the air pressure affects the speed and landing position of the ball that is hot out.

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HYPOTHESIS:

I hypothesised that if the air pressure, that is used to project the ball, is changed, then the balls projectile speed/strength changes according to that and can therefore be measured and the landing position can be predicted accurately.

 

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MATERIAL:

• Vernier projectile launcher    

• small metal balls

• (optional) Laptop

• (optional) Time of Flight pad

• LabQuest

• "container" to catch the ball

 

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PROCEDURE: 

1. Set up equipment.

2. Chose an angle for the ball to be launched out of.

3. Chose an air pressure value for the ball to be launched at.

4. Load the projectile launcher with a ball.

5. (optional) Run a few practice shots to make sure everything is being recorded properly.

6. Fire the ball.

7. Mark its landing spot.

8. Increase/decrease the air pressure (remember by how much).

9. Fire the ball.

10. Mark its new landing spot.

11. Repeat steps 8-10 a few times (using the same value to increase/decrease the air pressure each time).

12. Using the data collected, mathematically work out how much the balls distance increases by the air pressures increase.

13. (optional) Mark a landing spot and, using the data, change the air pressure to try and hit that spot.

14. (optional) Change the air pressure and, using that data, try to mark the correct landing position.

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ANALYSIS:

When the air pressure is increased or decreased, the balls distance will increase or decrease according to the air pressure as well. If the air pressure is increased/decreased by the same amount consistently, the balls distance increases/decreases by the same amount every shot.

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CONCLUSION:

The landing position of a metal ball that is shot from a projectile launcher can be accurately measured and predicted.
 

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SOURCE OF ERROR:

   Some things that may have affected the experiment are that the air pressure and the distance the ball travels isnt 100% consistent, I dont quite understand why this is, but one of my guesses is that the ball sometimes might spin differently when its shot, this will, change the speed/ direction of the ball. This is commonly known as the Magnus effect, which is a particular manifestation of Bernoulli's theorem. I dont quite see how a problem like this might be fixed.