GRAVITY&

GRAVITATIONAL FORCE

PRESENTD BY :MISS PRITI SINGHAL

Gravity is a force between all objects.

Gravity

WHAT IS GRAVITY

GRAVITY DEFINED

Gravity is the tendency of objects with mass to accelerate towards each other .

Gravity is one of the four fundamental forces in nature.

THE HISTORY OF GARVITY

HISTORY

Sir Isaac Newton wrote the Law of Gravitation in 1687(after 45 years of Kepler)

The size of the force also depends on the distance between the objects.

The size of the force depends on the mass of the objects.

LAW OF GRAVITY

Gravity

The force of gravity on something is called is weight ,Because it is a force it is measured in Newtons.

Mass is a measure of the amount of material an object is made of.It is measured in Kilograms.

Weight is the force of gravity of an object. It is measured in NEWTONs.

Mass and Weight

MASS WEIGHT

Mass is a physical property of matter that explains how much matter is in an object.

Mass does not change when gravity changes

Weight is a force which is calculated by multiplying the acceleration of gravity times mass.

Weight can change when gravity changes.

GRAVITATION FORCE IS THE ATTRACTION FORCE BETWEEN TWO OR MORE OBJECTS .

IT IS PROPORTIONAL TO THE PRODUCT OF MASS OF THE OBJECTS .

IT IS INVERSLY PROPORTIONAL TO THE SQURE OF THE DISTANCE BETWEEN THE OBJECTS.

THE FORCE ACTS IN THE DIRECTION OF THE LINE CONNECTING THE CENTRES OF THE MASSES

WHAT IS GRAVITATION FORCE

F1 F2

r

F1=F2= Gm1m2\

r2

We represent the Gravitational force by the symbol of F

and its unit is NEWTON.

NEWTON LAW OF GRAVITATIONAL FORCE

M1 M2

G is a constant which value remains constant at any

place ,so that’s why it called the UNIVERSAL GRAVITATIONAL

CONSTANT and the value of G is:

G = 6.67x10-11 N m2/kg2

Universal Gravitational is also known as an Inverse Square.

WHAT IS G?

Ques . Find the value of Gravitational Force ,when the masses of the two objects are 2 kg and 6 kg, and the distance between them is 4 m.(G= 6.67x10-11 N m2/kg2)

F = Gm1m2\

r2

F = 6.67x10-11 x 2 kg x 6 kg

4 x 4 =5.0025x10-11 N

Example to Find the Gravitational Force

PRITI SINGHAL

COMPUTER INSTRUCTOR

UPS KAILASPUR

SAHARANPUR

THANKS