Hypothesis
Variables
Experiments
Conclusions
Steps of the Scientific Method
100
  • What is a hypothesis? 
  • A testable explanation or prediction based on observations or prior knowledge
100
  • Observation, question, hypothesis, experiment, conclusion.
  • The factor the scientist changes on purpose
100
  •  Why should scientists conduct multiple trials? 
  • Multiple trials improve reliability and help reduce the effect of unusual results or random error.
100
  • What should a conclusion explain? 
  • What the results show and whether the evidence supports the hypothesis.
100
  • Which step involves noticing or describing something in the world that prompts an investigation? 
  • Observation
200
  • Why must a hypothesis be falsifiable?
  • There must be a possible result that could show the hypothesis is not supported.
200
  • What is the dependent variable?
  • The factor the scientist measures or observes.
200
  •  In a fair test, what should happen to controlled variables? 
  • They should be kept the same.
200
  • If the data do not support a hypothesis, does that prove the experiment was useless?
  •  No; the results still provide evidence and can guide a revised hypothesis or future investigation.
200
  • In which step do scientists state what they want to find out?
  • Question
300
  •  Is “Plants are interesting” a testable hypothesis? 
  •  No; it is an opinion that makes no measurable prediction
300
  •  In a test of how ramp height affects the distance a paper ball travels, what is the independent variable?
  • Ramp height.
300
  •  A student changes ramp height and measures travel distance. What is one important procedure to keep consistent? 
  •  Release the same paper ball from the same starting point without pushing it.
300
  • What evidence should students use in a conclusion?
  • Specific measurements, patterns, comparisons, or averages from the data.
300
  •  What step involves using evidence to determine what the results mean?
  • Analysis
400

Which hypothesis is better designed: “Plants grow better with water” or “If a bean plant receives 50 mL of water daily, then its average height after four weeks will be greater than that of a plant receiving 10 mL daily”? Explain why.

  • The second hypothesis is better because it makes a specific, measurable, and testable prediction with clearly defined conditions and a measurable outcome.
400
  •  In a test of how ramp height affects the distance a paper ball travels
  •  
  • Name two controlled variables in the paper-ramp investigation.
  •  Any two appropriate factors kept the same, such as the ramp, paper ball, release point, or surface.
400
  •  Why should measurements be recorded during, rather than after, an experiment?
  • Recording immediately preserves accurate data and reduces memory errors
400
  •  A paper ball traveled farther from the taller ramp in most trials. What is a reasonable conclusion?
  • The data support the prediction that increasing ramp height increases travel distance, while noting that the conclusion is limited by the data and procedure.
400
  • Put these steps in a logical order: conclusion, experiment, observation, hypothesis, question
  • Observation, question, hypothesis, experiment, conclusion.
500
  • A hypothesis predicts that increasing ramp height will increase travel distance, but the results show no consistent pattern across repeated trials. What can the scientist conclude about the hypothesis, and what should happen next?
  •  The data do not support the hypothesis under the tested conditions; the scientist should examine the procedure and data for error, revise the hypothesis or conditions if warranted, and conduct further controlled testing.
500
  • In a fair test, a student changes both ramp height and paper-ball mass, then measures travel distance. Identify the variables and explain the design problem
  • Ramp height and paper-ball mass are both independent variables, travel distance is the dependent variable, and the design confounds the effects of the two changes; the student should change only one factor while keeping the other controlled.
500
  •  A student tests three ramp heights but uses a different paper ball and release technique for each height. The average distances differ. Can the student claim ramp height caused the difference? Explain.
  • No. The paper ball and release technique are uncontrolled variables that could explain the results, so the student must repeat the experiment with the same ball type and consistent release procedure.
500
  • Most trials show greater distance from a taller ramp, but one trial at the shortest ramp produces the greatest distance. How should a conclusion handle this result?
  •  It should report the overall pattern and acknowledge the outlier, use all of the data rather than discarding it without justification, and state that the evidence generally supports the prediction but is not perfectly consistent.
500
  • A study begins with an observation, develops a hypothesis, tests it, and finds data that do not support it. Which scientific method steps should the scientist revisit, and why?
  • The scientist should revisit the hypothesis and, if needed, the question or experimental design; the results provide evidence for refining the explanation or procedure rather than simply repeating the same conclusion.
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