I am doing a project on paper planes, and I don't know what they mean by indepent and dependent variable, I know I want to see what flies further, a light weight paper plane or a plane made of heavier paper, but then they ask about the dependent and independent variable can you please help.

An independent variable is the potential stimulus or cause, usually directly manipulated by the experimenter, so it could also be called a manipulative variable.

A dependent variable is the response or measure of results.

Extraneous variables — other than the independent variable — potentially can affect the dependent variable, so they must be controlled. If possible, you try to keep them constant between the experimental and control group.

The experimental group receives the independent variable.

The control group is similar to experimental, except it does not receive the independent variable. Extraneous variables are balanced between experimental and control groups.

Types of experiments

1. Single blind gives the control group a placebo — a substance that is inert, it has no physical effect. Subjects don't know if they are in experimental or control group to reduce placebo effect, a change in behavior solely due to believing that you are getting the independent variable.

2. Double blind keeps both subjects and experimenter ignorant of group setup. Distribution of the independent variable and placebo are controlled by third party. This controls for experimenter bias and self-fulfilling prophecy, which means that experimenters with particular expectations are likely to consciously or unconsciously to bias the experiment and influence it to conform to their expectations.

As an example, suppose you want to find out if fluorides reduce dental cavities. You would find two groups, trying to control the extraneous variables. Extraneous variables are found by surveying previous research in the area. In this case, you would match the groups in terms of previous history of cavities, diet and dental hygiene habits including how and how often they brush their teeth.

The experimental group would get toothpaste with the independent variable, the fluoride, while the control group would not have the fluoride in their toothpaste. The toothpaste without the fluoride would be the placebo.

The dependent variable would be the number of cavities after participating in the experiment for a time. The dependent variable indicates the results, but it is not the results. At the end of the experiment, both groups could have no change in cavities or one of the groups could have a greater reduction in cavities. (Of course, if the fluoride increased cavities, you wouldn't want to use it.) All of these varied results would be indicated in terms of the dependent variable.

If only the subjects do not know who is getting the fluoride, it is a single blind experiment. If both the subjects and experimenter do not know, it is a double blind.

Although this is more than you asked for, I hope the additional information will be helpful.

two factors affect the amount of friction what are those two factors

Sure! When conducting a research project, it's important to understand the concepts of independent and dependent variables.

The independent variable is the factor that you manipulate or change in your experiment. In your case, the independent variable would be the weight of the paper used to make the plane. You are intentionally creating two different types of paper planes: one with lightweight paper and another with heavier paper.

The dependent variable, on the other hand, is the factor that you measure or observe to see how it is affected by the independent variable. In your project, the dependent variable would be the distance each paper plane flies. After launching both planes, you will measure how far each one flies to determine their performance.

To summarize:

Independent variable: The weight of the paper used to make the plane.

Dependent variable: The distance each paper plane flies.

By comparing the distance the lightweight and heavy paper planes travel, you will be able to determine which type of paper plane flies further.

Remember, it's important to have only one independent variable in your experiment to clearly identify its impact on the dependent variable.