Exploring the Investigative World of Science — Class 8 MCQs with Answers
Class 8 CBSE Science · Chapter 1
72 practice questions · 24 Easy · 24 Medium · 24 Hard · Updated
Practise the most important Class 8 CBSE Science questions from Chapter 1, "Exploring the Investigative World of Science". You get 9 timed quizzes made from 72 NCERT-based MCQs, with answers and explanations. The questions are split into 24 Easy, 24 Medium and 24 Hard. Warm up on the basics, then move on to the exam-level questions that top scorers in CBSE Board exams get right.
To score well in "Exploring the Investigative World of Science", focus on clear concepts in physics, chemistry and biology basics. Each MCQ here is timed and uses exam-style marking (+4 correct, −1 wrong, 0 skipped). This helps you stay accurate when time is short, just as real papers need. Every question has a short explanation, so a wrong answer becomes a quick lesson. It is the fastest way to fix gaps before a test.
Use this chapter for focused revision. Start with the Easy set to check your basics on Exploring the Investigative World of Science, then move to Medium and Hard to practise applying them. Your accuracy, streaks and XP save automatically. This chapter also adds to your overall Class 8 Science mastery score. 14 sample questions are solved in full below, with the answer and a worked explanation. Sign in free to start practising.
Exploring the Investigative World of Science — important questions & MCQs with answers (Class 8 Science)
14 solved questions from this chapter's difficulty levels, each with its answer and explanation.
- Q1Easy
A scientific investigation usually begins with:
A.memorising factsB.expensive equipmentC.curiosity and careful observation✓ CorrectD.guessing randomlyAnswer: C. curiosity and careful observation
Explanation: Science starts with curiosity and careful observation of the world, not with memorised facts or costly equipment — noticing something surprising is what sparks the first question.
- Q2Easy
A good scientific investigation starts by asking a:
A.conclusionB.final answerC.question✓ CorrectD.storyAnswer: C. question
Explanation: Investigations start from a question, not a ready-made conclusion or story — the question is what tells you what to observe and test next.
- Q3Easy
In an experiment, a thing you deliberately change is a:
A.resultB.factor you control✓ CorrectC.conclusionD.mistakeAnswer: B. factor you control
Explanation: A factor you deliberately change in an experiment is the one you control — it is set on purpose, unlike a result, which is what you observe afterward.
- Q4Easy
To measure how fast a puri puffs, you record the:
A.colour name onlyB.your feelingsC.time in seconds✓ CorrectD.the recipeAnswer: C. time in seconds
Explanation: Recording puffing speed as time in seconds gives a number you can measure and compare across trials, unlike a colour name or a feeling.
- Q5Easy
To do simple experiments, what do you mainly need?
A.a fancy laboratoryB.curiosity and careful observation, not a fancy lab✓ CorrectC.costly chemicalsD.a powerful computerAnswer: B. curiosity and careful observation, not a fancy lab
Explanation: Simple experiments need curiosity and careful observation, not a fancy lab, costly chemicals, or a computer — a kitchen works fine for watching and testing everyday events.
- Q6Easy
Observing carefully means using your:
A.imagination onlyB.memory onlyC.senses to notice details✓ CorrectD.calculator onlyAnswer: C. senses to notice details
Explanation: Careful observation means actively using your senses — sight, smell, touch — to notice real details, not relying on imagination or memory alone.
- Q7Medium
A sensible order for a simple investigation is:
A.explain, then ask a questionB.observe, then forget itC.ask a question, experiment, observe, then explain✓ CorrectD.guess, then stopAnswer: C. ask a question, experiment, observe, then explain
Explanation: A sensible investigation order is: ask a question, run the experiment, observe what happens, then explain the result — explaining before testing would mean guessing without evidence.
- Q8Medium
The questions a scientist asks in an investigation should be:
A.impossible to answerB.about nothingC.just opinionsD.focused and testable✓ CorrectAnswer: D. focused and testable
Explanation: Useful scientific questions are focused and testable by observation or experiment — vague, unanswerable, or opinion-based questions cannot be investigated this way.
- Q9Medium
In the puri experiment, dropping the dough vertically or at an angle tests the effect of:
A.the flour typeB.the oil temperatureC.the way of dropping✓ CorrectD.the thicknessAnswer: C. the way of dropping
Explanation: Dropping the dough vertically or at an angle isolates the effect of the dropping method itself, since every other factor stays the same in that comparison.
- Q10Medium
A scientific conclusion should be based on:
A.the observations and data collected✓ CorrectB.personal likesC.a coin tossD.the teacher's moodAnswer: A. the observations and data collected
Explanation: A scientific conclusion must follow from the observations and data actually collected during the experiment, not from personal preference or chance.
- Q11Medium
Before designing an experiment, a scientist first decides:
A.what to change and what to observe✓ CorrectB.the final answerC.the marks to giveD.nothingAnswer: A. what to change and what to observe
Explanation: Before designing an experiment, a scientist decides what to change and what to observe — this planning step sets up the fair test before any frying or measuring begins.
- Q12Hard
If your results are different each time you repeat, you should:
A.repeat more and look for a pattern✓ CorrectB.pick the answer you likeC.stop investigatingD.change the question secretlyAnswer: A. repeat more and look for a pattern
Explanation: Different results each time call for more repeats and a search for a pattern in the data, rather than picking whichever answer you prefer.
- Q13Hard
The factor a scientist deliberately changes is the:
A.dependent variableB.controlC.observationD.independent variable✓ CorrectAnswer: D. independent variable
Explanation: The factor a scientist deliberately changes is the independent variable — it is set on purpose, distinct from the dependent variable, which is measured as the outcome.
- Q14Hard
If a plant grows taller with more light, a reasonable conclusion is:
A.soil colour matters mostB.sunlight affects plant height✓ CorrectC.water is uselessD.light has no effectAnswer: B. sunlight affects plant height
Explanation: Taller growth with more light supports the conclusion that sunlight affects plant height — the data links the one thing changed to the outcome measured.
Key concepts: Exploring the Investigative World of Science (Class 8 Science)
This opening chapter is about how science actually works — systematic investigation. Science starts with curiosity and careful observation, turning everyday wonders (like why a puri puffs up) into focused, testable questions. You learn to plan an experiment by deciding what to change and what to observe, to run a fair test by changing only one thing at a time, to record both qualitative (yes/no) and quantitative (measured) observations, and to draw conclusions from the evidence — while remembering that science is always evolving as new questions arise.
- Systematic investigation
- A careful, step-by-step way of answering a question: observe, ask a testable question, experiment, record, and explain — the heart of how science works.
- Careful observation
- Using the senses to notice details of what actually happens; good observation is the solid ground on which investigation is built.
- Scientific question
- A focused, testable question such as 'what happens to a puri if the oil is hotter?' that can be explored by observation or experiment.
- Hypothesis
- A possible explanation put forward to be tested by an experiment; if the evidence disagrees, the hypothesis is revised or rejected.
- Variables you control
- The factors you can change in an experiment, such as the dough thickness, flour type or oil temperature; the deliberately changed one is the independent variable.
- Variables you observe
- The outcomes you watch or measure, such as whether a puri puffs or how many seconds it takes; the measured outcome is the dependent variable.
- Fair (controlled) test
- An experiment in which only one factor is changed at a time while all others are kept the same, so any effect can be traced to that single change.
- Qualitative vs quantitative
- Qualitative observations describe without numbers (the oil smoked), while quantitative observations are measured numbers (it took 8 seconds).
- Recording data
- Keeping careful notes of everything observed, even surprises, so results can be compared, patterns spotted and conclusions justified.
- Drawing conclusions
- Explaining the results from the evidence collected, not from personal likes; a conclusion follows from the data.
- Science is evolving
- Each answer opens new questions and ideas change as evidence grows, so even a simple puffing puri is not yet fully understood.
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Start this chapter free →Exploring the Investigative World of Science — FAQs
What are the key concepts in Class 8 Science Exploring the Investigative World of Science?+
This opening chapter is about how science actually works — systematic investigation. Science starts with curiosity and careful observation, turning everyday wonders (like why a puri puffs up) into focused, testable questions. You learn to plan an experiment by deciding what to change and what to observe, to run a fair test by changing only one thing at a time, to record both qualitative (yes/no) and quantitative (measured) observations, and to draw conclusions from the evidence — while remembering that science is always evolving as new questions arise. Key ideas include Systematic investigation, Careful observation, Scientific question, Hypothesis, Variables you control, Variables you observe.
What does Class 8 Science Chapter 1 (Exploring the Investigative World of Science) cover on XamBaaz?+
It has 72 NCERT-based MCQs on "Exploring the Investigative World of Science": 24 Easy, 24 Medium and 24 Hard. Together they make 9 timed quizzes, and you never get the same set twice. Every question has an instant explanation. They help you prepare for CBSE Board exams.
Are these "Exploring the Investigative World of Science" questions free to practise?+
Yes. Sign in with Google to practise "Exploring the Investigative World of Science" free. Full unlimited access is ₹999/year. One year from the day you pay. You stay in Class 8 till 31 March; on 1 April your account moves up to Class 9 and the rest of your year carries over. No chapter is charged separately.
How should I revise "Exploring the Investigative World of Science" for the exam?+
Start with the Easy quiz to check your basics, then try Medium and Hard to practise applying them. There are 9 timed quizzes on this chapter, so you can come back for a fresh set instead of one you have seen. Read each explanation, retry the questions you miss, and track your accuracy until it stays high.
Are these "Exploring the Investigative World of Science" MCQs available with answers?+
Yes. 14 sample questions are shown here in full, each with the correct option and a step-by-step "Why" explanation. Sign in free with Google to start practising, with instant scoring.
Is there negative marking in the "Exploring the Investigative World of Science" quizzes?+
Yes. The timed quizzes use exam-style marking: +4 for a right answer, −1 for a wrong one and 0 for a skip. MHT-CET and CBSE board papers have no negative marking. Our mocks for those are scored their way.
What are the important questions from Exploring the Investigative World of Science (Class 8 Science)?+
The questions that matter most test Systematic investigation, Careful observation, Scientific question, Hypothesis, Variables you control, Variables you observe. This page shows 14 solved important MCQs with answers and explanations. Sign in to practise all 72 questions on the chapter as timed quizzes.
Is there an online quiz for Exploring the Investigative World of Science?+
Yes — Class 8 Science Exploring the Investigative World of Science has timed online quizzes at Easy, Medium and Hard levels, with instant scoring and a worked explanation on every question. The first quiz on the chapter is free.