# Bart believes that mice exposed to microwaves will become extra strong (maybe he's been reading too much Radioactive Man). He decides to perform this experiment by placing 10 mice in a microwave for 10 seconds. He compared these 10 mice to another 10 mice that had not been exposed. His test consisted of a heavy block of wood that blocked the mouse food. he found that 8 out of 10 of the microwaved mice were able to push the block away. 7 out of 10 of the non-microwaved mice were able to do the same.

Identify the-
11. Control Group

12. Independent Variable

13. Dependent Variable

14. What should Bart's conclusion be?

15. How could Bart's experiment be improved?

1. 👍
2. 👎
3. 👁
4. ℹ️
5. 🚩
1. Control group- non microwaved mice

Independent Variable- exposure to the microwave

Dependent Variable- the weight of the block of wood

Conclusion- Microwaved mice will be extra strong.

Improvement- Repeat the experiment a few more times and compare the results.

1. 👍
2. 👎
3. ℹ️
4. 🚩
2. It might help to review the above concepts.

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.

I hope this helps a little more. Thanks for asking.

1. 👍
2. 👎
3. ℹ️
4. 🚩
3. Owls hunt mice. An owl hears a mouse. How will the owl react?

A.
The owl will fly away.

B.
The owl will swoop down to catch the mouse.

C.
The owl will stare at the mouse.

D.
The owl will scream to alert other owls.

1. 👍
2. 👎
3. ℹ️
4. 🚩
4. B duh

1. 👍
2. 👎
3. ℹ️
4. 🚩