Scientific Method and SI units

In science, it is an organizational tool that takes the form of a series of procedures.

There are six parts to the scientific method. The steps are state the problem,

gather information, form a hypothesis, perform an experiment, analyze data and

report results.

To start the scientific method, a scientist has to observe something that they know nothing

about. So they state the problem. The problem is stated in the form of a question. Next the

scientist begins to gather information about the problem so that they can understand the

problem a little more.

Once they have information, the scientist is going to come up with a hypothesis. A

hypothesis is a prediction that can be tested. A hypothesis has to always be something that you

can test. After the scientist makes up their hypothesis, he or she is going to perform an

experiment to test the hypothesis. A hypothesis is stated in an “If…then…” format.

Next you have to perform an experiment. There some steps that need to be followed that use controlled

conditions. There are going to be groups that are tested in every experiment. One is the variable group. This group is the factor that the scientist is testing for in the experiment. The other group is the control group. This group is the standard used to compare with the outcome of a test. The control group is going to have all the same

things happening to it as the variable group (experimental group) except for the one factor that you

are testing to solve the problem.

The next step is analyze data. The scientist will look at all the data that was collected in the experiment and

come up with an answer to the problem. This answer will either prove that the hypothesis is true or false. The

last step in the scientific method is to report results. After the scientist has looked at all the data, he or she will tell other scientists about the results of his or her experiment. This will either be written in a scientific

paper or presented to other scientists.

The answers to your problems can either be considered a scientific theory or a scientific law. A scientific theory

is an explanation of things or events based on many observations. This means that many experiments had to come to the same conclusion. Scientific theories can be changed if new data is found that shows that it is false. A scientific law is based on repeating data that tells us how nature works. Experiments have all had the same

conclusions many, many times. A law can also be changed but not as easily as a theory.

Scientists use a system called an SI (International System of Units) to

measure things. This chart will show you some of the SI units and will help you to convert one unit to another.

Prefixes Meaning

kilo- One thousand (1000)

hecto- One hundred (100)

deca- Ten (10)

deci- One-tenth (0.1)

centi- One-hundredth (0.01)

milli- One-thousandth (0.001)

SI metric units of Length:

1000 millimeters (mm) 1 meter (m)

100 centimeters (cm) 1 meter (m)

10 decimeters (dm) 1 meter (m)

10 millimeters (mm) 1 centimeter (cm)

1000 meters (m) 1 kilometer (km)

What is the formula for area?

Area = Length x Width

We measure mass in grams. We will learn how to use a triple beam balance at another time. When measuring volume of a liquid we are going to use a graduated cylinder. How do you know how much of the liquid you have? You look at the liquid in the graduate cylinder at eye level. You read the level that the liquid is at the meniscus, which is a curve at the surface of a liquid. This will only happen in glass graduated cylinders. You will not see one when you use a plastic one.

When you are trying to find the volume of an object that is cube like, you are going to get the measurements of the length, width and height of the cube. The formula for volume is:

Volume = length x width x height

Temperature can be measured in 3 different scales. They are

Kelvin, Fahrenheit and Celsius.  

Kelvin Fahrenheit Celsius

Boiling point of water

     

100 C

Human body temperature

     

Freezing point of water

   

32 F  

0 C

Absolute zero    -273.15 C

373 K 212 F

310 K 98.6 F 37 C

273 K

0 K -459.67 F

The

End