Scientific Investigations — Reading Comprehension

Scientific investigations are essential for building knowledge about the natural world. Scientists use a step-by-step process called scientific inquiry to answer questions and solve problems. This process helps ensure that conclusions are based on reliable evidence, not just opinions or guesses. One common example of scientific inquiry is testing which brand of paper towel can absorb the most water. Such investigations help us make informed choices in everyday life and deepen our understanding of scientific principles.

Steps of Scientific Inquiry

The process of scientific inquiry typically begins with careful observation. Observations are facts or events that can be noticed with the senses or measured. For example, you might notice that some paper towels seem to absorb more water than others. This observation leads to a question: Which paper towel brand absorbs the most water? Next, scientists form a hypothesis—a testable statement predicting the outcome. For example, you might hypothesize, “Brand A will absorb more water than Brand B or C.” The next step is designing a fair test, known as an experiment. A fair test means changing only one variable at a time while keeping all other factors constant. In our paper towel example, the variable is the brand, while the amount of water, size of towels, and timing must stay the same.

Collecting Data and Drawing Conclusions

During the experiment, scientists collect data by measuring the amount of water each brand absorbs. For accuracy, they might repeat the test several times and calculate the average results. The data are then organized in charts or graphs for analysis. By comparing the numbers, scientists see which brand performed best. If Brand A consistently absorbs 30% more water than Brand B, the evidence supports the hypothesis. However, if the results are mixed, scientists may need to revise their hypothesis or repeat the experiment. The final step is forming a conclusion based on the data. The conclusion should directly relate to the evidence collected.

Real-World Applications and Broader Principles

Scientific investigations are not limited to paper towels. Engineers use similar methods to test new materials for safety, while doctors rely on controlled experiments to determine if medicines are effective. In all cases, fair testing and careful data analysis are crucial for making reliable discoveries. The principles of scientific inquiry—such as forming hypotheses, controlling variables, and analyzing data—are part of a larger scientific framework known as the scientific method. This approach helps scientists around the world communicate results, build on each other’s work, and solve complex problems that impact society, technology, and the environment.

Scientific investigations demonstrate how evidence leads to knowledge. By following systematic steps, anyone can test ideas and draw conclusions based on facts. This process is the foundation of scientific thinking and helps us make better decisions in daily life and in addressing global challenges.

Interesting Fact: Some scientists repeat experiments hundreds of times to be sure their results are accurate and reliable!

What is the first step of scientific inquiry?

In the paper towel experiment, what is considered the variable?

Why is it important to keep all but one variable the same in an experiment?

What do scientists use to compare the results of their experiments?

What does the word 'hypothesis' mean in the passage?

What is a 'fair test' according to the passage?

If the results do not support the hypothesis, what should a scientist do?

Doctors and engineers use scientific investigations in their work.

A conclusion should be based on the data collected.

Which of these best describes the scientific method?