NCAE Scientific Ability and Critical Thinking 1 — Questions and Answers
Question 1: Which of the following best describes the scientific method?
- A set of rigid rules that must be followed exactly
- A systematic approach to investigating phenomena through observation and experimentation (Correct answer)
- A way to prove that a hypothesis is always correct
- A method used only in laboratory settings
Correct answer: A systematic approach to investigating phenomena through observation and experimentation
The scientific method is a systematic approach that involves observation, hypothesis formation, experimentation, and analysis. It is flexible and can be applied in various settings, not just laboratories.
Question 2: A student notices that plants near the window grow taller than those in the corner. What is the most logical next step in the scientific method?
- Conclude that light makes plants grow taller
- Form a hypothesis about the relationship between light and plant growth (Correct answer)
- Tell the teacher about the observation
- Move all plants to the window
Correct answer: Form a hypothesis about the relationship between light and plant growth
After making an observation, the next step in the scientific method is to form a hypothesis. This hypothesis would then need to be tested through a controlled experiment before drawing conclusions.
Question 3: Which variable is deliberately changed by the researcher in an experiment?
- Dependent variable
- Controlled variable
- Independent variable (Correct answer)
- Confounding variable
Correct answer: Independent variable
The independent variable is the one that the researcher deliberately changes or manipulates to observe its effect. The dependent variable is what is measured as a result of that change.
Question 4: In an experiment testing whether fertilizer affects rice yield, what is the dependent variable?
- The type of fertilizer used
- The amount of water given
- The yield of rice harvested (Correct answer)
- The type of rice planted
Correct answer: The yield of rice harvested
The dependent variable is the outcome that is measured in the experiment. In this case, the rice yield is what changes in response to the fertilizer application.
Question 5: What is the purpose of a control group in an experiment?
- To increase the number of test subjects
- To provide a baseline for comparison with the experimental group (Correct answer)
- To ensure the experiment takes longer
- To eliminate all variables from the study
Correct answer: To provide a baseline for comparison with the experimental group
A control group serves as a baseline that does not receive the experimental treatment. By comparing the experimental group to the control group, researchers can determine the effect of the independent variable.
Question 6: Which of the following is an example of a qualitative observation?
- The temperature is 32 degrees Celsius
- The solution turned blue after adding the reagent (Correct answer)
- The plant grew 5 centimeters in one week
- There are 15 fish in the pond
Correct answer: The solution turned blue after adding the reagent
Qualitative observations describe qualities or characteristics that cannot be measured numerically, such as color, texture, or smell. The color change of a solution is a qualitative observation.
NCAE Scientific Ability and Critical Thinking 1
Which of the following best describes the scientific method?