1. Newton’s Law of Universal Gravitation
Presented by
Vineetha I V
Physical Science
Roll No : 20
2. • The idea of gravity was Introduced by Sir Isaac
Newton in the late 1600’s
• He was a scientist who combine ideas
to explain how the universe operates
3. How He Discovered it…?
• Newton’s law of Gravitation was discovered while he
watched an apple fall from a tree.
• The force that pulled the apple to the ground was
the same with which apple attracted earth.
4. All Matter Is Affected by Gravity
• Because of gravity you are being pulled toward your book,
your pencil, and every other object around you.
• You exert an attractive force on everything around you and
everything is exerting an attractive force on you.
• This attractive force is called gravity.
• All objects experience an attraction toward all other objects
in this universe.
5. Gravitational Force
Gravitation force depends on two things:
• The mass of the two objects
• The distance between the two objects
6. Gravitational Force and Mass
• Earth attracts an elephant more than
a cat.
• Earth attracts coconut more than an apple.
• Earth’s gravitational force is greater than that of
moon.
Gravitational force increases as mass
increases.
8. Gravitational Force and Distance
• Gravity between you and the earth is greater than
the gravity between you and the sun.
Gravitational force decreases as distance increases.
9. • Gravitational force is inversely proportional to the
square of distance between the masses
10.
11. • All objects in the universe attract each other through
gravitational force. Every body in the universe attracts every
other body with a force which is directly proportional to the
product of their masses and inversely proportional to the
square of the distance between them.
F ∝ M1M2
d2
F = G M1M2
d2
G = Gravitational Constant & G = 6.67x10-11 Nm2/kg2
This is Law of Universal Gravitation
Universal : applies to all objects!!!
• The force acts in the direction of the line connecting the
centers of the masses.
