The heat beneath your feet

[Mlopez8912]

Hello Science Buddies,
I am writing to you on behalf of my daughter. So we have bought all the piece for her science project but haven't been able to find a Nail 1/8 in Diameter we went to Lowes and they said thats a very small diameter are there any suggestions? Also, We are having difficulty properly describing the Control, independent & dependent variables in the project. I was hoping to get some feed back thank you.

[scibuddyAK]

Hi,

I'd be happy to help you out with determine your control, independent variable, and dependent variable. However, I would need to know a little more about your project before I can answer--what exactly is your daughter testing? It seems like she's doing this project: https://www.sciencebuddies.org/science- ... #procedure
If this helps you out at all, a control is a standard for comparison, an independent variable is what you're manipulating or testing, and a dependent variable is what is affected based on the changes you make to the independent variable (you may be measuring this, most probably). It seems to me like your independent variable(s) (factors you're testing) looks like mainly the number of holes around the edge, the number of pinwheel stripes, and whether or not the foil has a can. The dependent variable seems like the number of complete spins the pinwheel makes in 20 seconds since this is what you're recording data for as a result of changing the other parameters (independent variables), but I'd verify this against the definitions to be sure.

I'm not sure where you can get a nail 1/8 of an inch in diameter--hopefully some other Experts can chime in on this. I'll keep looking.

In the meantime, I hope this has helped you get started!
Please post back with any more questions.

Thanks!

[Mlopez8912]

This helps tremendously. She is doing "The power of heat is right under your feet." So after doing some more research I'd like your feedback about these following statements. Our overall Question would be " How does a Geothermal Power Plant Work?" Our Hypothesis would be "If I use a geothermal power plant then the amount of energy created will be stronger than not using a geothermal power plant." (How does that sound so far we've had difficulty formulating a concise hypothesis) In testing this hypothesis i think we should focus on her independent variable being using the can as a geothermal power plant versus not using one and her dependent variable being the number of Pinwheel spins. Her controlled variables would be the number of holes in the aluminum foil being consistent and the stove setting. How do you think we are doing so far?

[scibuddyAK]

Hi,

Good start! I do have a few comments, though, so hopefully you find these helpful. I believe that your independent variable would be a more specific factor you're testing. That way you have a more direct link between your independent variable and your dependent variable, the number of pinwheel spins--a clear link is very important, so pick an independent variable accordingly. I think you can alter a specific factor (i.e. just as an example, something like "size of pinwheel") to more clearly observe its effects on number of pinwheel spins, since it makes a much stronger experiment than just testing the difference between having a power plant or not. The controls look great! (:

Just like the independent and dependent variables, the question and hypothesis need to have the same clear link connecting them. So perhaps a question along the lines of: "What factors affect how a geothermal power plant works?" and then a hypothesis would address what factors affect this and perhaps how.

Hope this helped!

[Mlopez8912]

Thanks again, I can't thank you enough after revising some of the points mentioned this is what we have come up with (unfortunately we dont have two different size pinwheels so) Our Question will be: "Do surface holes affect how a geothermal power plant works? Hypothesis: "If I increase the number of surface holes around my power plant, then the number of pinwheel spins will decrease." Control: height of pinwheel,stove setting, number of holes under the can and in the can itself. Independent variables: the number of holes around the edge of the pot (I'd say repeating the experiment 3x with at least 3 different amount of holes around the outside) Dependent variable: the complete # of pinwheel spins. I have used the table created in the experiment but I am not sure if I still should include both with a power plant and without. I'm not sure if I have to tie this into my question and hypothesis or just as an added interest? Please help thanks.

[scibuddyAK]

This looks great! Exactly how it should be done!

You may tie it into your question if you're testing it, but you may just want to include it in your research to have a more cohesive project (one main, well-investigated focus). Do remember that if you add it in to your question/hypothesis, you'd have to create a separate set of tests with another independent var/dependent var.

Good luck!