NCERT Solutions for Class 8th Science Chapter 1 Exploring the Investigative World of Science
Updated on 2026-09-19
About this chapter
Grade 6 showed us that science begins with wonder ; Grade 7 showed us that science keeps evolving . Grade 8 puts the two together and takes us into the investigative world of science — we no longer only learn new facts, we learn how to find new facts . Investigation means more than looking and asking simple questions. You ask a focused question , design a simple experiment to answer it, and then use your own observations to improve your understanding. The chapter is a guided tour of the whole year — microorganisms in a drop of water, staying healthy with food, exercise, medicines and vaccines; the heating and magnetic effects of electric current; force, pressure, winds and cyclones; the particles that make up matter; elements, compounds, mixtures and solutions; reflection, mirrors and lens
- Chapter opening
- Entering the Investigative World of Science
- A tour of the year
- Phases of the Moon and the first calendars
- Thinking like a scientist
- Keeping notes, and the new questions an experiment raises
Quick revision
| Term | What it means | Where it comes in the chapter | Everyday example |
|---|---|---|---|
| Investigation | A planned way of answering a question — observing, experimenting, explaining — not just looking at something | Pages 2, 7 | Finding out what makes a puri puff |
| Scientific question | A focused question that can actually be tested by an experiment | Page 6 | “What changes the way a puri puffs up when fried?” |
| What we can change or control | The condition you deliberately alter in an experiment | Page 6 | Dough thickness, size, type of flour, oil temperature, way of dropping |
| What we can observe or measure | What you watch, count or time to see whether your change made a difference | Pages 6–7 | Did it puff (yes/no); time taken to puff (seconds) |
| Fair test | Changing only one thing at a time and keeping every other condition the same | Pages 6–7 | Same thickness, same way of dropping — only the oil temperature changed |
| Keeping notes | Recording everything you see, smell and hear, not only the numbers | Page 7 | “Did the oil splatter, smell, or smoke?” |
| Systematic investigation | The full cycle — question → experiment → observation → fresh questions — used in all science, simple or complicated | Page 7 | One round of frying leads to the next question |
| Root symbol | Bottom of the left-hand pages — the solid foundation of careful observation and of our heritage | Page 2 | Staying grounded in what you actually see |
| Kite symbol | Top of the right-hand pages — curiosity must take flight to explore the unknown | Page 2 | Letting your ideas soar to new horizons |
| Chaitra | First month of the Indian national (Shaka) calendar, shown in the chapter’s calendar picture | Page 4 | Chaitra 2025 ran from 22 March to 20 April 2025 |
| An open question | A question science has not yet fully answered | Page 7 | Exactly why a puri puffs is still not fully understood |
Exercises
- Chapter opening — Probe and ponder Page 1
- Entering the Investigative World of Science — In-text Questions Page 2
- A tour of the year — In-text Questions Page 3
- Phases of the Moon and the first calendars — In-text Questions Page 4
- Thinking like a scientist — In-text Questions Page 6
- Keeping notes, and the new questions an experiment raises — In-text Questions Page 7