The Scientific Method


Every year in the spring, large numbers of frogs appear in the mud near the river Nile. They aren´t
there in dry weather, so in the past ancient Egyptians used to believe that the mud produced the
frogs. The problem is they didn´t test their belief scientifically.

The first step in the scientific method is to observe the world around you. For example, Newton
noticed that an apple fell down, not up. The Egyptians did this part alright. Not all observations
can be done directly by your senses. Some observations require the use of an instrument.

Step two is to ask yourself a question based on observations. “Why does the apple go down?”
“Where do the frogs come from?”  Then you start interpreting your observations, deducing or making
an inference.

One day you may find a possible answer - a hypothesis. “Objects are pulled to the ground by an
invisible force.” “Mud produces frogs.”


To continue, use one of the following words to fill in the gaps.

conduct      conclusions      confirmed      enough      found      masses      may      rate


But it isn´t  ^1_______________ just to think of an answer to a question and believe it´s true. You
have to discover some evidence that confirms your hypothesis. So, next step is to test your ideas
with experiments and more observations. Galileo believed that two objects with different
^2___________ would fall at the same  ^3________________. So, the story goes, he carried out an
experiment. He dropped a heavy ball and a light ball from the Leaning Tower of Pisa, and
^4______________ his belief. The Egyptians never did any experiments on their mud-frog hypothesis,
so they never ^5____________ out it was false.

If you do an experiment only once, you  ^6_____________ make a mistake. So you need to repeat your
experiments to make sure you get the same results, and analyze your findings statistically to check
they are significant. You also need to make any necessary changes to your hypothesis and
^7________________more experiments. Carefully record everything you do so other scientists can
duplicate your work and check your  ^8_______________.


Here are some more words to complete the last part of this text:

Accept     evidence     field      float      law      predictions

A hypothesis with lots of experimental  ^1 ________________ becomes a theory.  A theory which has
been confirmed many times is a scientific law. The great thing about hypotheses, theories and laws
is that you can use them to make  ^2 ___________________. The ^3 ___________ of gravity predicts
that astronauts should  ^4 ________________ in space. And they do.

Chemists and physicists, geologists and biologists, researchers in every laboratory in every  ^5
_______  of research use the scientific method. They do not  ^6 _____________  untested
observations.


Task    Name some instruments which are used in your field.







Adapted partly from the text in Maturita Activator, Pearson Education Limited, 2009