Science notes of class 9

science notes of class 9, science notes of all chapter wise full detailed explain, all topics are explained in full detail and in simple language. science notes like physics notes class 9, chemistry notes, class 9, biology notes class 9. Here is the following chapter and subjects described below.
When we prepare for the examination book reading is not worth that time. we have to revision a notes not a whole book. so we should make a simple notes and in easy language but also in our language.

science notes class 9 chapter wise ( Physics )

Unit of measurement and time
Motion
Force and laws of motion
Gravitation
Work energy and power
Sound

science notes class 9 chapter wise ( chemistry )

Matter in our surrounding
Is matter around us pure
Atom and molecules
Structure of atom

science notes class 9 physics chapter 1

Unit of Measurement and time

Physics:- The study of nature and natural things.

It is the made of greek word ” Fusis” means natural things and nature.
It means that physics is the study of nature and its laws.
Physics is the foundation of engineering and technology.
Physics is based in experiment when experiments are done then it measure with the help of physical quantity.
Quantity means it represents the number.

Physical quantity:- It is represent of the physical laws in the term id quantity.

It is of two types
Scalar quantity and vector quantity.
Scalar quantity means it has only magnitude not direction.
vector quantity means it has both magnitude and as well as direction.

Units

It is of two types

Fundamental unit
Derived unit

Fundamental unit:- It is not depend another unit, three fundamental unit are mass, length and Time.
Derived unit:- It is depend in fundamental unit.

system of unit are four types

Mks system:- In this system Length, Mass and Time are expressed in meter, Kilogram, and Second.
Fps system:- In this system Length, Mass and Time is expressed in Foot, Pound, second.
CGs system:- In this system Length, Mass and Time is expressed in Centimeter, Gram, second.
S.I system;- ( international System of Unit ) In S.I system having seven fundamental unit.

Science notes class 9 chapter 2

Motion

In physics a things which can see, touch and feel is called object or body.
It is the branch of physics which deals with the study of the object at rest and in motion.

Object in rest

A body is said to be rest if it does not change its position with respect to its surrounding with the passage of time.

Object in motion

If the position of the body changes its state with respect to its surrounding then body is called in motion.

Rest and motion are relative terms

Rest and motion are relative terms because object can be at rest with respect to one things and in motion with respect to some other things at the same time, so motion is not absolute, it is relative. for example—

Suppose you are sitting in a train which is moving then we are at rest with respect to the other passenger sitting in that compartment but in motion with respect to the objects on the ground.
Our house is at rest with respect to the other house on the earth but it is in motion with respect to an observer on the moon.

Types of motion

One dimension, two dimension motion, three dimension motion.

One dimension motion:-

The motion in a straight lines is called one – dimension motion.
Moving of bus in a straight line.
Falling of an apple from tree.
If only co – ordinate is used from three co – ordinate x, y and z then the motion is one dimension motion.

Two dimension motion;-

Motion in a plane is called two dimension motion.
If only two co – ordinate is used from three co – ordinate x, y and z then it is called two dimension.
The motion of object in horizontal and vertical circle.
The earth revolving around the sun.
S carom coin in motion.

Three dimension motion;-

Motion in space is called three dimension motion.
If all co – ordinate is used then it is called three dimension motion.

Position:-

If particles on the origin then its position will be zero.
If particles move along the positive direction of x – axis then its position positive.
If particles moves along the negative direction of x – axis then position negative.