# Designing an experiment, i no how, just need a formular

• me2
In summary, you should not do this experiment. It is much more complicated and easier to just purchase a pressure regulator and launch a marble from an inclined plane.
me2
here is the task;
Design a labatory experiment to investigate how the range of a projected object depends on the angle of projectory and find the optimum angle

i was thinking of getting dome tubing, and ataching a preasurises CO2 canister (fire extingiser basicaly), and put something in there to regulate the preasure it fires the projectile with, then just ajust the tube and record the angles of projectory and horizontal displacement etc

so i just woundered if there are any fancy (but usable) formulas i could put in?

thanks

If you ignore air resistance the formulae required are elementary. Have you studied any kinematics?

any wat? nope don't think so (if i have i don't no it by that word) sorry

So you have never seen formulae like;

$$s=ut + \frac{1}{2}at^2$$

that would be a no, although i think i might have done something similar, thanks anyway, I've spoken to a friend n they haven't used any formulas so i might give it a miss

thanks for you time anywayz

Do you actually have to do this experiment?

nope just plan it

Well, if you actually have to create this experiment, there are much easier (and cheaper) ways to go about it. All you need is an inclined plane, a rubber band, and a marble. Attach the rubber band to the end of the inclined plane, put on the marble, and launch the marble from various angles, starting from 0 and going in increments of about 5° until you get to 90. Best of luck.

What I would do (much simpler, and doesn't require pneumatics, which guarantees something will explode, if not accidentally then because you know you're going to want to blow it up at the end and write it off as a lab expense :D), is first, get a tube with one end closed. second, take a plate with a bar sticking through it, and glue a spring onto it so the spring wraps around the bar. Drill a hole through closed end of the tube, large enough for the bar on the plate to fit through, but small enough so the spring can't. Notice you can now pull on the bar, and when you let go, the plate will shoot forward because of the spring (perhaps attach something to the end of the bar so it doesn't fly back out). Using this as a projectile device is much more convenient, because the force is easily calculable based on how far back you pull the bar, so you don't need to hand-wave and say you put a pressure regulator inside of your apparatus

i like the last idea, but I am over half way through writing my original idea up and i don't have the time to start again, n like u said, more chance of blowing something up which reminds me i ought to put that in the safty precautions

## 1. What is the purpose of designing an experiment?

The purpose of designing an experiment is to test a hypothesis and gather data to support or reject it. It allows for a controlled and systematic approach to understanding a phenomenon or problem.

## 2. What are the key elements of a well-designed experiment?

A well-designed experiment should have a clear and testable hypothesis, a control group, an experimental group, a standardized procedure, randomization, and a sufficient sample size.

## 3. How do I determine the appropriate sample size for my experiment?

The appropriate sample size depends on the type of experiment, the expected effect size, and the desired level of statistical power. There are various online calculators and statistical software that can help determine the appropriate sample size.

## 4. What is the importance of randomization in an experiment?

Randomization helps to eliminate bias and ensure that the results of the experiment are not influenced by any extraneous variables. It also allows for the generalization of the results to a larger population.

## 5. How can I improve the reliability and validity of my experiment?

To improve reliability, it is important to repeat the experiment multiple times and ensure consistency in the procedures and measurement tools. To improve validity, it is important to use appropriate control groups, minimize confounding variables, and use reliable and valid measurement tools.