Drop a coin into a glass of water and it seems to float higher than it really is. A pencil in a glass looks bent. After the rain, a rainbow splits sunlight into colours. All of these happen because light does not always travel in a straight line. Chapter 10 of the DAV Class 8…
Right now your eyes are doing something amazing. Light from this screen enters them, gets focused into a tiny picture, and your brain turns it into words you can read, all in a fraction of a second. Chapter 11 of the DAV Class 8 Science book explains how the human eye works, what can go…
Look around you. Your school bag, water bottle, toothbrush, raincoat and even some of your clothes are likely made from something that did not grow on a plant or come from an animal. They are made in factories from chemicals. Chapter 13 of the DAV Class 8 Science book is about these man-made materials: synthetic…
Somewhere between childhood and adulthood, the body goes through a big set of changes. Your height shoots up, your voice changes, your skin behaves differently, and your feelings can swing more than before. None of this is random. Chapter 15 of the DAV Class 8 Science book explains what adolescence is, which chemical messengers (hormones)…
When you plug in a phone charger, you are using the heating and magnetic effects of electric current. But electricity can also cause chemical changes, and that is the story of Chapter 16 in the DAV Class 8 Science book. The chapter explains which liquids conduct electricity, what happens when current passes through them, and…
An earthquake can strike without warning, and in a few seconds it can bring down buildings and change a landscape. Chapter 18 of the DAV Class 8 Science book explains why the ground shakes, how we measure that shaking, and how we can protect ourselves. This post gives easy answers to every question in the…
We breathe about twenty thousand times a day, and every one of those breaths depends on the quality of the air around us. Chapter 19 of the DAV Class 8 Science book explains what spoils that air, what the polluted air does to people, buildings and the planet, and what we can do about it….
Every sound you hear, from a school bell to a mosquito buzzing near your ear, begins with something shaking back and forth. Chapter 12 of the DAV Class 8 Science book is all about this idea: how sound is made, how it travels, and what makes one sound loud, shrill or unpleasant. This post gives…
Water looks simple, but keeping it clean is one of the biggest challenges any town or city faces. Chapter 20 of the DAV Class 8 Science book explains what pollutes our water, why that is dangerous, and how water is made safe to drink. Below you will find the answers to every exercise in the…
Reproduction is the one thing every living species has to get right, and Chapter 14 of the DAV Class 8 Science book explains how animals manage it. This article gives you the answers to every exercise in the chapter, plus the extra practice questions, written in plain language so you can understand the idea behind…