NCERT Solutions for Class 5th The World Around Us Chapter 7 Pinwheel — Activity 6
Book page 123–124 Updated on2026-09-19
Q1.
Pinwheel — 1. Take a square piece of paper. 2. Draw its two diagonals with the help of a ruler. 3. Now, you have four equal parts. 4. Cut halfway along each of the four lines. 5. Fold each corner and pin it to the stick as shown in the image. 6. Now, hold your pinwheel in the wind. If there is no wind, hold it up and run with it.Steps 1 to 5 of making the pinwheel, as pictured on page 123.
Answer
How to make it, step by step:
Cut a square of stiff paper, about 15 cm on each side. A thin card or an old greeting card works best.
With a ruler, draw a line from one corner to the opposite corner. Do the same for the other pair of corners. These two lines are the diagonals — the lines that join opposite corners. They cross at the centre.
The square is now divided into four equal triangles.
Cut along each diagonal from the corner towards the centre — but stop halfway. Do not cut right up to the centre, or the paper will fall into four pieces.
You now have four loose corner points. Take one point from each cut and fold it in to the centre. Hold all four down together with your finger.
Push a pin through all four folded points and the centre of the paper, and then into the side of a stick, a pencil eraser or a thin bamboo.
Loosen the pin a little so the paper can spin freely.
Hold it up in the wind. If there is no wind, hold it up and run.
Square → diagonals → four half-cuts → fold four corners in and pin them to a stick.
If it will not spin: the pin is too tight — pull it back a little. Or the folded corners are too heavy — fold in only the tips. Or the paper is too soft and floppy — use a stiffer card.
Q2.
What happens to your pinwheel?
Answer
The pinwheel spins round and round. When the wind is strong it whirs fast and its colours blur together. When the wind drops it slows and stops. If there is no wind, it starts spinning the moment you run with it.
What I do
What the pinwheel does
Hold it still in calm air
It does not move at all
Hold it in a gentle breeze
It turns slowly
Hold it in a strong wind
It spins fast and makes a soft whirring sound
Run with it, holding it up
It spins, because I have made the air rush past it
Blow on it from the side
It turns; blow from the other side and it turns the other way
Why it happens: Each folded corner makes a small slanting flap, like a tiny sail. The moving air cannot pass straight through the flap, so it pushes on the slant. Every flap gets pushed the same way round, and the whole wheel turns. So the moving air has done work — which means the wind is a source of energy. That is what the book concludes: the pinwheel rotated, the paper burned and the water wheel spun, and all these show that the wind, the Sun and water are sources of energy that make things work.
A pinwheel grown big: A windmill is nothing but a giant pinwheel. The wind pushes its long blades round, and the turning is used to make electricity. Old sailing ships used the same wind — traders from Gujarat and Tamil Nadu sailed to Africa, Arabia and Southeast Asia using the power of the wind.