Class 4 EVS (Our Wondrous World) Chapter 7, How Things Work, opens Unit 4 (Things Around Us) with curious siblings Meera and Dhruv testing everyday toys and objects — investigating why coins, bangles, and DIY cardboard tops spin, and why some objects float while others sink depending on material and shape.
What Class 4 EVS Chapter 7 Covers
Spinning Objects & Making DIY Spinners (Tops) tests coins, bangles, pencils, stones, and erasers to see which spin smoothly; builds cardboard-and-toothpick spinners; and observes how centre balance, stick length, and disc shape affect spinning.
Floating and Sinking & Designing Better Boats experiments with objects in water to see which float or sink, discovers how hollow shapes (like a bowl or paper/clay boat) float even when a flat lump sinks, and tests how much load a boat can hold.
Exercises in Chapter 7
- Let us Reflect, Think and Answer, and in-text observation questions.
- Hands-on classroom experiments, nature trail logs, and community interviews.
Read Class 4 EVS Chapter 7 Online
More Chapters
- Previous: Chapter 6: Happy and Healthy Living
- Next: Chapter 8: How Things are Made
- Hindi medium: Class 4 EVS Chapter 7 PDF in Hindi (Hamara Adbhut Sansar)
- All EVS chapters and the other Class 4 books: Class 4 NCERT books 2026-27
- All Class 1 to 12 NCERT Textbooks: NCERT Books PDF (Class 1–12)
FAQ
Why does a coin or wooden top spin smoothly while an eraser does not?
Objects that are round or symmetrical around a central point spin smoothly around their axis, whereas an uneven, rectangular block like an eraser wobbles and stops quickly.
How does shape affect whether something floats or sinks?
A tight ball of clay or foil may sink in water, but when the same piece is shaped into a hollow bowl or boat that displaces more water, it floats and can even carry small weights.