Class 9 Science - Force and Laws of Motion | Complete Notes with Examples, Numericals, Tricks & Exam Questions

Chapter 9: Force and Laws
of Motion
Introduction to Force

Force is a push or pull that can change the
state of motion or shape of an object.

Effects of Force:

V Can change the speed of an object
V Can change the direction of motion
V Can change the shape of an object
V Can bring an object to rest

, Types of Forces
1. Contact Forces:

These forces act only when two objects are in
contact.
V Muscular Force - Applied by muscles (e.g.,
lifting a bag)
V Frictional Force - Opposes motion (e.g.,
brakes of a bicycle)

2. Non-contact Forces:

These forces act without direct contact.
v Gravitational Force - Attraction between
objects (e.g., apple falling from a tree)
V Magnetic Force - Acts between magnets
y Electrostatic Force - Force due to charged
particles