In Science, a theory is a reasonable explanation of observed events that are related. A theory often involves an imaginary model that helps scientists picture the way an observed event could be produced. A good example of this is found in the kinetic molecular theory, in which gases are pictured as being made up of many small particles that are in constant motion.

   After a theory has been publicized, scientists design experiments to test the theory. If observations confirm the scientists’ predictions, the theory is supported. If observations do not confirm the predictions, the scientists must search further. There may be a fault in the experiment, or the theory may have to be revised or rejected.

   Science involves imagination and creative thinking as well as collecting information and performing experiments. Facts by themselves arc not science. As the mathematician Jules Henri Poincare said: "Science is built with facts just as a house is built with bricks, but a collection of facts cannot be called science any more than a pile of bricks can be called a house."

   Most scientists start an investigation by finding out what other scientists have learned about a particular problem. After known facts have been gathered, the scientist comes to the part of the investigation that requires considerable imagination. Possible solutions to the problem are formulated. These possible solutions are called hypotheses. In a way, any hypothesis is a leap into the unknown. It extends the scientist's thinking beyond the known facts. The scientist plans experiments, performs calculations, and makes observations to test hypotheses. For without hypotheses, further investigation lacks purpose and direction. When hypotheses are confirmed, they are incorporated into theories.

In the last paragraph, what does the author imply is a major function of hypotheses?

Câu hỏi liên quan

• If you have a desire to travel, when does the writer suggest that you do it?

• Where in the passage is the name of Pippin’s hometown mentioned?

• The pronoun “they” in the second paragraph refers to_____.

ZUNIA12

• According to the passage, what does a constricted and harsh voice indicate?

• According to the passage, what is implied about tea harvesting?

• The word “These” in paragraph 3 refers to__________.

• Computers are used most for ______________

• According to the passage, cell phones are especially popular with young people because ...............

• Which sentence best expresses the main idea of the second paragraph?

• Animals found desert living possible only _____

• The author’s main purpose is to...

• What can be inferred from the passage about supernovas?

•  The word “metamorphosis” in paragraph 2 is closest in meaning to ................

• The word “perishable” in paragraph 1 is closest in meaning to ............

• The phrase "the wee hours" in paragraph 3 probably refers to the period of time _____.

• The passage was written to ..........

• Which of the following is NOT supported by the passage?

• The passage is mainly about ............

• The word "they" in the passage refers to ______.

• The word "supported" in paragraph 2 is closest in meaning to _______.