Class 9 / Science
Class 9 Science Motion Notes
Concept notes on distance, displacement, speed, velocity, acceleration, and motion graphs.
mediumRevision notes
Key points
- Distance is the actual path length, while displacement is the shortest change in position.
- Speed has magnitude only, while velocity has magnitude and direction.
- Acceleration is the rate of change of velocity.
Speed and velocity
Speed tells how fast an object moves. Velocity also tells the direction of motion.
Uniform motion means equal distances in equal intervals of time.
Graphs
A distance-time graph helps students understand whether an object is at rest, moving uniformly, or changing speed.
A steeper line generally shows greater speed.
Quick practice
- Find speed if distance is 120 m and time is 20 s.
- Write one difference between speed and velocity.
- What does a horizontal distance-time graph show?
Related practice
For schools
Run your school with VyasNex School Management System
Use VyasNex for attendance, fees, report cards, parent communication, records, and daily school administration.