1. GRAVITY & GRAVITATIONAL FORCE
PRESENTD BY :
MISS PRITI SINGHAL

2. WHAT IS GRAVITY
Gravity is a force between all objects.
Gravity

3. 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.

4. THE HISTORY OF GARVITY

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

6. LAW OF GRAVITY
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.

7. Mass and Weight
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.

8. 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.

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

10. WHAT IS GRAVITATION FORCE
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

11. NEWTON LAW OF GRAVITATIONAL FORCE
F F2 r
F1=F2= Gm1m2\ r2
We represent the Gravitational force by the symbol of F
and its unit is NEWTON. M1 M2

12. WHAT IS G? Universal Gravitational is also known as an Inverse Square.
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.

13. Example to Find the Gravitational Force
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
=5.0025x N

14. THANKS
PRITI SINGHAL
COMPUTER INSTRUCTOR
UPS KAILASPUR
SAHARANPUR