Gravitation – Class 9 Science Notes

By the end of this lesson, readers will:

  • – Introduction
    • Gravitation
    • Gravitational Force
  • – Free Fall
  • – Acceleration due to Gravity
  • – Mass and Weight
  • – Thrust and Pressure
  • – Archimedes’ Principle
    • Buoyant Force
  • – Relative Density

Gravitation:

The force which attracts every object towards another object is called Gravitation.

Note: This is the universal force between every object and is present everywhere, no matter how far it is.

-Gravitational Force: The force between every two objects due to their masses is called gravitational force.

The formula for gravitational force was given by Newton:

If the only reason for the fall of an object is gravity, then it is called free fall.

Examples: sky diving, fruits fall from tree, balls, etc.

If an object’s acceleration is due to free fall, then it is called acceleration due to gravity (g).

Formula:

g =

Mass:

The amount of matter in an object is called its mass.

Mass is the same everywhere, whether on Earth or the moon.

It is a scalar quantity.

Weight:

The gravitational force applied to an object is called its weight.

Weight can be different at different places.

It is a vector quantity.

Formula:

Thrust:

Thrust means the perpendicular force applied on a surface.

  • It is a vector quantity. 
  • Its SI unit is Newton.

Pressure

The force applied on a unit area of ​​an object is called pressure.

  • Its SI unit is N/m2, which is also called a Pascal (Pa).

Formula

Examples of Thrust and Pressure:

Buoyant Force:

When an object is immersed in a liquid substance such as water, etc., an upward force is applied to it, which is called the “Buoyant Force”.

What is Archimedes’ Principle?

When an object is immersed in a liquid like water, etc., the buoyant force acting on it is equal to the weight of the liquid displaced by the object.

The ratio of the density of an object to the density of water is called relative density.

Formula:

  • Coming Soon…

MCQs

Coming Soon…

Fill in the blanks.

Coming Soon…

Match

Coming Soon…

Questions and Answers:

Coming Soon…

Coming Soon…

Provide downloadable materials for learners to review:

  • – PDF Guide: “Coming Soon”
  • – Cheat Sheet: “Coming Soon”
  • – Video Source: “JNG ACADEMY
  • – Articles: “Blog Page

What is gravitation?

The force which attracts every object towards another object is called Gravitation.
Note: This is the universal force between every object and is present everywhere, no matter how far it is.

What are the difference between mass and weight?

Mass: The amount of matter in an object is called its mass.
Note: Mass is the same everywhere, whether on Earth or the moon.
It’s a scalar quantity.

Weight: The gravitational force applied to an object is called its weight.
Note: Weight can be different at different places.
It’s a vector quantity.

What are the difference between thrust and pressure?

Thrust: Thrust means the perpendicular force applied on a surface.
It’s a vector quantity. 
Its SI unit is Newton.

Pressure: The force applied on a unit area of ​​an object is called pressure.
Its SI unit is N/m^2, which is also called a Pascal (Pa).

What do you mean by “Archimedes’ Principle“?

Archimedes’ principle states that when an object is immersed in a liquid like water, etc., the buoyant force acting on it is equal to the weight of the liquid displaced by the object.

Blogging for Beginners

WordPress for Beginners

WordPress Freelancing Mastery Course

Leave a Comment