The Wonderful World of Science Part 1: MCQs (Q1–Q25)
Part 1 — Questions 1–25
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Science is best described as:
A. A list of facts to be memorized.
B. A way of finding out about the world by observing and experimenting. ← Correct answer: B
C. A type of fiction writing.
D. Only about chemistry and physics.
Explanations:
A) Incorrect — science is not mere memorization; it’s a process.
B) Correct — science involves observation, asking questions, testing (experimenting) and drawing conclusions.
C) Incorrect — science relies on evidence, not imagination alone.
D) Incorrect — science includes biology, earth science, etc., not only chemistry/physics. -
Which of the following is the first step in a simple scientific investigation?
A. Drawing conclusions.
B. Recording results.
C. Asking a question or observing a problem. ← Correct answer: C
D. Publishing a book.
Explanations:
A) Incorrect — conclusions come after investigation.
B) Incorrect — recording happens during/after experiments.
C) Correct — investigations start with curiosity, an observation or question.
D) Incorrect — publishing is not the first step. -
An observation is:
A. A wild guess.
B. Something we notice using our senses. ← Correct answer: B
C. Always a proven fact.
D. A synonym for experiment.
Explanations:
A) Incorrect — an observation is based on sensing, not guessing.
B) Correct — observations use sight, hearing, touch, smell or taste (carefully).
C) Incorrect — observations provide data but need interpretation and testing.
D) Incorrect — experiments use observations but are not identical. -
Quantitative observations are those that:
A. Use words like “big” or “beautiful”.
B. Include numbers or measurements (e.g., 10 cm, 2 litres). ← Correct answer: B
C. Are always opinions.
D. Cannot be repeated.
Explanations:
A) Incorrect — those are qualitative descriptions.
B) Correct — quantitative = measurable quantities.
C) Incorrect — quantitative data are objective.
D) Incorrect — measurements can be repeated for reliability. -
Which instrument is best for measuring the length of a pencil?
A. Measuring cylinder.
B. Thermometer.
C. Ruler (scale). ← Correct answer: C
D. Stopwatch.
Explanations:
A) Incorrect — measuring cylinder measures volume.
B) Incorrect — thermometer measures temperature.
C) Correct — ruler or scale measures length in cm or mm.
D) Incorrect — stopwatch measures time. -
The SI unit of mass commonly used in school laboratories is:
A. Metre.
B. Kilogram (kg) or gram (g). ← Correct answer: B
C. Celsius.
D. Second.
Explanations:
A) Incorrect — metre is unit of length.
B) Correct — mass measured in grams or kilograms.
C) Incorrect — Celsius measures temperature.
D) Incorrect — second measures time. -
Which device would you use to measure the temperature of water?
A. Balance.
B. Thermometer. ← Correct answer: B
C. Beaker.
D. Ruler.
Explanations:
A) Incorrect — balance measures mass.
B) Correct — thermometer measures temperature in °C.
C) Incorrect — beaker holds liquid but doesn’t measure temperature.
D) Incorrect — ruler measures length. -
A hypothesis is:
A. A final proven law.
B. A tentative explanation or possible answer that can be tested. ← Correct answer: B
C. Always true.
D. The same as raw data.
Explanations:
A) Incorrect — hypotheses are tested and may be revised.
B) Correct — it’s a testable idea that guides experiments.
C) Incorrect — it may be disproved.
D) Incorrect — data are what you collect to test a hypothesis. -
Which of these is an example of a qualitative observation?
A. 25 mL of milk.
B. 30°C temperature.
C. The liquid is cloudy. ← Correct answer: C
D. Mass = 50 g.
Explanations:
A/B/D) Incorrect — these are quantitative (numbers).
C) Correct — “cloudy” describes appearance without numbers (qualitative). -
To reduce errors in an experiment, you should:
A. Do the experiment only once.
B. Repeat the experiment and take average readings. ← Correct answer: B
C. Change measurement units randomly.
D. Ignore anomalous results.
Explanations:
A) Incorrect — one trial may be unreliable.
B) Correct — repetition improves reliability; averaging reduces random error.
C) Incorrect — consistent units are essential.
D) Incorrect — anomalous results should be checked, not ignored. -
A measuring cylinder is used to measure:
A. Mass of solids.
B. Length of objects.
C. Volume of liquids (in mL or L). ← Correct answer: C
D. Temperature.
Explanations:
A) Incorrect — mass measured by balance.
B) Incorrect — length by ruler.
C) Correct — graduated cylinders show liquid volume.
D) Incorrect — thermometer measures temperature. -
Why do scientists use tables and graphs?
A. To hide their data.
B. To organize and present data clearly for analysis. ← Correct answer: B
C. To make experiments longer.
D. Because numbers are not useful.
Explanations:
A) Incorrect — purpose is clarity, not hiding.
B) Correct — tables/graphs help spot patterns and trends.
C/D) Incorrect. -
Which of the following is a safety rule in the laboratory?
A. Taste chemicals to identify them.
B. Wear safety goggles when working with chemicals or heating. ← Correct answer: B
C. Run in the lab.
D. Leave burners unattended.
Explanations:
A) Incorrect — never taste chemicals.
B) Correct — goggles protect eyes; safety rules prevent accidents.
C/D) Incorrect — running/ leaving equipment unattended is dangerous. -
The difference between observation and inference is that:
A. Observation is seeing; inference is interpreting why something happened. Correct answer: A ← Correct answer: A
B. Inference is always a measurement.
C. Observation is a guess.
D. They are identical.
Explanations:
A) Correct — observation records what senses detect; inference explains or interprets observations.
B/C/D) Incorrect — inferences may be logical conclusions, not raw measurements; observations are not guesses. -
Which of the following pairs are units of time?
A. Metre and kilogram.
B. Second and minute. ← Correct answer: B
C. Litre and ampere.
D. Celsius and mol.
Explanations:
A/C/D) Incorrect — those are units of length/mass/volume/electric current/temperature/amount.
B) Correct — second and minute measure time. -
Which tool helps us see very small objects like cells?
A. Telescope.
B. Microscope. ← Correct answer: B
C. Measuring tape.
D. Vernier caliper.
Explanations:
A) Incorrect — telescope is for distant objects.
B) Correct — microscope magnifies tiny objects for observation.
C/D) Incorrect — measuring tools, not magnifiers. -
A spring balance measures:
A. Volume.
B. Temperature.
C. Force (often read as weight). ← Correct answer: C
D. Speed.
Explanations:
A/B/D) Incorrect — different quantities.
C) Correct — spring balance measures force due to gravity; commonly used to estimate weight. -
In an experiment, the variable that you change on purpose is called the:
A. Dependent variable.
B. Control variable.
C. Independent variable. ← Correct answer: C
D. Random variable.
Explanations:
A) Incorrect — dependent variable changes in response.
B) Incorrect — control variables are kept constant.
C) Correct — independent variable is the one you manipulate.
D) Incorrect — random variables are not controlled. -
The dependent variable in an experiment is:
A. The variable you change.
B. Always equal to zero.
C. The quantity you measure or observe as a result. ← Correct answer: C
D. The variable you ignore.
Explanations:
A) Incorrect — that’s the independent variable.
B/D) Incorrect.
C) Correct — dependent variable depends on changes in independent variable. -
Which of the following best describes a ‘control’ in an experiment?
A. A random sample.
B. A standard setup that is kept unchanged to compare results. ← Correct answer: B
C. A test that uses no instruments.
D. A measurement error.
Explanations:
A/C/D) Incorrect.
B) Correct — control helps isolate effect of the independent variable. -
When recording data you should:
A. Use messy handwriting.
B. Record values clearly with units and date. ← Correct answer: B
C. Only remember results without writing.
D. Write false data if results are unexpected.
Explanations:
A/C/D) Incorrect — clarity and honesty are essential.
B) Correct — include units, labels and conditions. -
Which is an example of technology derived from science?
A. Storytelling.
B. Mobile phones and microscopes. ← Correct answer: B
C. Paintings only.
D. Legends.
Explanations:
A/C/D) Incorrect — arts and culture are different domains.
B) Correct — technology like phones is based on scientific knowledge. -
Which sense should NOT be used to test unknown chemicals in lab?
A. Sight.
B. Touch.
C. Taste. ← Correct answer: C
D. Smell carefully only if instructed and safe.
Explanations:
A/B) Use with caution (touch usually avoided for chemicals).
C) Correct — tasting chemicals is hazardous and forbidden.
D) Smell is risky; only used with safe protocols (wafting). -
Peer review in science means:
A. Scientists ignore others’ work.
B. Other scientists check and evaluate results before acceptance. ← Correct answer: B
C. Students watching peers play.
D. Hiding data.
Explanations:
A/C/D) Incorrect.
B) Correct — peer review ensures validity and reliability. -
Which statement is TRUE about models in science?
A. Models are full-size replicas only.
B. Models are simplified representations used to explain or predict phenomena. ← Correct answer: B
C. Models always give exact truth.
D. Models are never useful.
Explanations:
A) Incorrect — models can be diagrams, mathematical equations, etc.
B) Correct — models help visualize complex systems.
C/D) Incorrect — models approximate reality and have limitations.