Science Experiments

Variables are not constant. If they were constant they would be constant. For example, time is a variable in many graphs. Were it to be constant it would mean that time stopped.

In programming such as C++ you often make a constant variable. The term variable refers to a usable instance of a type such as an integer. Making it constant means that it is unchangable but you can still use in the same manner as a variable. It is good practice to use constant variables rather than writing the values directly in the code because if the constant value changes it only needs to be changed in one place. For example:

without constant variable:

if (screenWidth > 200) {

lineEnd = 200;

}

drawLine(0, lineEnd);

with constant variable:

const int MAX_SCREEN_WIDTH = 200;

if (screenWidth > MAX_SCREEN_WIDTH) {

lineEnd = MAX_SCREEN_WIDTH;

}

drawLine(0, lineEnd);

In practice the value may be spread over many files and a search for 200 may find many other results that may be the wrong value.

Constant variables also help indicate the intention of the code without needing a comment. In the above example, the 200 does not indicate that it is the maximum screen width.

Making the variable constant means that the compiler will show an error if you try to change it.

MAX_SCREEN_WIDTH = 400; // will cause error

It is common practice to use uppercase letters to indicate a constant variable.

he experiments tests that they think will help them investigate and answer their question

Another Perspective:

A scientist follows the scientific method, exactly.

. Observing

2. Classifying

3. Inferring

4. Predicting

5. Measuring

6. Communicating

7. Using Space/Time Relations

8. Defining Operationally

9. Formulating Hypotheses

10. Experimenting

11. Recognizing Variables

12. Interpreting Data

13. Formulating Models

The first of the science process skills, observation, involves noting the attributes of objects and situations through the use of the senses. Classification goes one step further by grouping together objects or situations based on shared attributes. Measurement involves expressing physical characteristics in quantitative ways. Communication brings the first three skills together to report to others what has been found by experimentation.

Inference and prediction are the more sophisticated of the science process skills. Beyond simply seeing and reporting results, scientists must extract meaning from them. These skills can involve finding patterns in the results of a series of experiments, and using experience to form new hypotheses. It is also essential for a scientist to be able to distinguish his objective observations from his inferences and predictions. This is because scientific inquiry and study depend on objectivity and an avoidance of hasty assumptions in experimentation.

All of the science process skills contribute to a larger purpose, namely problem solving. Problem solving is the reason for scientific inquiry, and forms the essence of it. A typical experiment wherein a scientist uses process skills and the scientific method will start with certain questions being asked. Based on prior knowledge and experience, the scientist will make an educated guess as to the answer or outcome. This hypothesis will guide the design and execution of an experiment.