Chapter 10: This World of Things
Chapter at a Glance
Khushi reaches school early and draws her sunlit classroom with a table, chair, door, window, blackboard and fan. She wonders where these things come from and what they are made of. The table and chair are made of wood, which comes from trees. The hinges, nails and latches are made of metals, which are taken out of rocks called ore dug from inside the Earth. The windowpanes are made of glass, which is made mostly from sand, and the switches are made of plastic.
Khushi notices that she can see flowers through the window glass. Things we can see through clearly, like glass, are transparent. Things we cannot see through, like wood, are opaque. Things we can see through partly, like butter paper or frosted glass, are translucent. Looking through coloured plastic or glass changes the colour of what we see. We should never look at the sun directly or through any object.
Different materials look, feel and sound different: metal is shiny and feels cold, and tapping a spoon on different objects makes different sounds. Wood is hard and rigid, while cloth is soft and flexible, so each material suits different things. Things can be solids (keep their shape), liquids (flow and take the shape of the container) or gases (float in and out). Things found in nature, like trees, birds, rocks and water, are natural. Things made by people, like clothes, shoes and tables, are artificial.
Word Meanings
| Word | Simple Meaning |
|---|---|
| Material | What a thing is made of, like wood or metal |
| Metal | A hard, shiny material like iron, copper or gold |
| Ore | Rock from which metals are taken out |
| Hinge | A metal joint on which a door swings |
| Alloy | A mixture of metals, like steel or brass |
| Transparent | Something we can see through clearly |
| Opaque | Something we cannot see through at all |
| Translucent | Something we can see through only partly |
| Rigid | Hard and not bending |
| Flexible | Able to bend easily |
| Solid | Keeps its own shape |
| Liquid | Flows and takes the shape of its container |
| Gas | Spreads out and has no fixed shape, like air |
| Natural | Found in nature |
| Artificial | Made by people |
Important Topics
1. Materials and Their Sources
| Object | Material | Source |
|---|---|---|
| Table, chair, door | Wood | Trees |
| Hinges, nails, latches | Metal | Ore dug from the Earth |
| Windowpane, bulb | Glass | Mostly sand |
| Electric switch | Plastic | Made from petroleum |
| Clothes | Cloth | Cotton plants, silk, wool |
| Pots | Clay | Soil |
2. Seeing Through Things
| Type | Meaning | Examples |
|---|---|---|
| Transparent | Can see through clearly | Window glass, clear water, spectacle glass |
| Translucent | Can see through partly | Butter paper, frosted glass, paper lampshade, thin cloth |
| Opaque | Cannot see through | Wood, metal, stone, a plate |
- Never look at the sun directly or through any object.
- Coloured glass or plastic changes the colour of things we see.
3. Properties of Materials
- Metal: shiny, smooth, feels cold, makes a ‘ting’ sound.
- Wood: hard and rigid; makes a ‘thak’ sound.
- Cloth: soft and flexible, good for clothes and curtains.
- Each object is made from a material that suits its use.
4. Solids, Liquids and Gases
| Solids | Liquids | Gases |
|---|---|---|
| Keep their shape | Flow; take the shape of the container | Spread out; float in and out |
| Stone, ice, spoon, bottle, bag | Water, ink, honey, milk | Air, smoke, steam |
5. Natural and Artificial Things
| Natural | Artificial |
|---|---|
| Tree, mango, bird, rock, water, air | Clothes, shoes, table, pencil, bag |
Question-Answers
Very Short Answer Questions
- What is Khushi’s table made of? Wood.
- Where do we get wood from? Trees.
- What are metals taken out of? Ore (rocks dug from the Earth).
- What is glass mostly made of? Sand.
- What are things we can see through called? Transparent.
- Is wood transparent or opaque? Opaque.
- Give an example of a translucent object. Butter paper (or a paper lampshade).
- Is honey a solid or a liquid? A liquid.
- Is steam a solid, liquid or gas? A gas.
- Are shoes natural or artificial? Artificial.
Short Answer Questions
Q1. What is the difference between transparent, translucent and opaque?
We can see clearly through transparent things like glass, only partly through translucent things like butter paper, and not at all through opaque things like wood.
Q2. Why are clothes not made of wood?
Wood is hard and rigid and cannot bend. Clothes need a soft, flexible material like cloth so that we can move comfortably.
Q3. Why can’t we make walls of water?
Water is a liquid and does not keep its shape; it flows away. Walls need solid materials like bricks, stones or wood.
Q4. What are natural and artificial things?
Things found in nature, like trees, birds, rocks and water, are natural. Things made by people, like tables, clothes and shoes, are artificial.
Long Answer Questions
Q1. Describe the things in Khushi’s classroom and what they are made of.
Khushi’s classroom has a table, chairs and a door made of wood, which comes from trees. The door hinges, nails and latches are made of metal, which is taken from ore dug out of the Earth. The windowpanes and bulb are made of glass, which comes mostly from sand. The electric switches are made of plastic.
Q2. Explain solids, liquids and gases with examples.
Solids have a fixed shape and do not flow, like a stone, ice, a spoon and a bottle. Liquids flow and take the shape of the container they are in, like water, ink and honey. Gases have no shape and spread out everywhere, like air, smoke and steam.
Textbook Exercise Answers
A. Three common materials: wood, metal and plastic (also glass and cloth).
B. How to find out if a shiny spoon is metal or painted. Tap it: metal makes a ‘ting’ sound. Touch it: metal feels cold. Scratch it gently: if paint comes off, it is painted.
C. Draw three natural things (tree, bird, flower) and three artificial things (chair, bag, pencil).
D. Match the pairs.
| Type | Object |
|---|---|
| Transparent | A glass used in spectacles |
| Translucent | A lamp shade made of paper |
| Opaque | A plate |
Chain game (sample)
| Khushi’s list | Material | Objects in my classroom or home |
|---|---|---|
| Table, chair, door | Wood | Pencil, cupboard, bed |
| Door hinges, nails | Metal | Spoon, key, fan |
| Windowpanes, light bulb | Glass | Tumbler, mirror, bottle |
| Electric switches | Plastic | Bucket, lunch box, pen |
| (new row) | Clay | Pot, diya, kulhad |
Sources: Wood – trees; Metals – ore from the Earth; Glass – sand; Cloth – cotton plants, silk, wool.
Odd pairs (sample)
| Object | Material | Reason |
|---|---|---|
| Umbrella | Paper | Paper tears when wet |
| Chair | Cloth | Cloth is too soft to hold weight |
| Cooking pot | Plastic | Plastic melts on the stove |
| Window | Wood only | We cannot see through wood |
| Shirt | Metal | Metal is hard and heavy |
Solids, liquids and gases
- Tray (solids): stone, ice, spoon, bottle, bag.
- Bottle (liquids): ink, honey, water.
- Balloon (gases): smoke, steam.
- Confusing objects: sand, sponge, clay.
When did Khushi draw her picture? Mango trees bear fruit in summer, so around June.