NCERT syllabus · 2 chapters
Lessons
One page per chapter, with review questions at the end that mark themselves.
Class 9
1 subject- GravitationOne rule explains a falling apple, the Moon's orbit, your weight, and why a ship of steel floats. This is that rule, and everything that follows from it.
- SoundSound is not a thing that travels — it is a squeeze passing through matter. That one shift explains why space is silent, why pitch is not loudness, and how a ship measures the sea floor.