Gravitation

This is the part one of gravitation chapter 10th MH board , it covers topics:-
Introduction
Centripetal force
Keplers law

1. Gravitation
WHAT IS GRAVITY?
By kenzo

2. Newton discovered gravity
Object falling
down
Satelite revolve
around earth
Planets stay
in there orbits

3. Grounded by Gravity: Why We Stay Firmly
Planted on Earth
We are able to walk abecause of gravity
astronauts fly because of the
absence of gravity in space

4. Gravity is a force of attraction that exists between any
two masses, any two bodies, any two particles or any
two objects in the universe.
Gravity Exists
Between these two
objects

5. The Pull of Gravity
Gravity is a force that pulls objects towards the center of the Earth
(or towards the center of any other celestial body).

6. Centripetal Force: Keeping Things Moving in Circles
velocity
Centripetal

Circular motion is when an object moves around in a circle,
with a constant distance to the center and a constant speed.
The force that keeps an object moving in a circle is called
centripetal force.
Centripetal means
centre seeking, i.e
the object tries to
go towards the
centre of the circle
because of this
force

7. Textbook questions

Q1) Do you think some force is constantly acting on the moon

Yes, some forces are constantly acting on the moon. The most significant force acting on the
moon is the force of gravity, which is responsible for keeping the moon in orbit around the
Earth.
Q2) What must be the direction of the graivty force on moon

The direction of the gravity force on the moon is towards the
center of the Earth.
Q3) How would its motion have been if no such force acted on it
If there were no gravitational force acting on the moon, it would move in a
straight line tangent to its current position.

9. "The orbit of a planet is an ellipse with the Sun at one of the foci"

Kepler's First Law: The Law of Ellipses

10. Foci 2Foci 1

11. Kepler's Second Law: The Law of Equal Areas
"The line joining the planet and the Sun sweeps equal areas in
equal intervals of time"
Planet moves faster near sun
Planet moves slow far from sun

13. Kepler's Second Law, also known as the Law of Equal Areas,
states that an imaginary line that connects a planet to the Sun
sweeps out equal areas in equal time intervals.

This means that as a planet moves around its orbit, it moves
faster when it is closer to the Sun and slower when it is farther
away. Despite the planet moving at different speeds at different
points in its orbit, the area it sweeps out in a given amount of
time is always the same.

14. Kepler's Third Law: The Relationship Between a Planet's
Orbital Period and its Distance from the Sun
"The square of its period of revolution around the Sun is directly
proportional to the cube of the mean distance of a planet from the Sun.''