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guys...i need ur help....please explain me kepler's three laws properly.....  
and one more question
if i want to drop a rubber ball and a metal ball from top of a building what woul be thier individual acceleration
Asked by asmita shah | 26 Aug, 2014, 09:31: PM
answered-by-expert Expert Answer
1. Kepler's laws govern the motion of planets around the sun and is known as Kepler's laws of planetary motion.
 
Kepler's first law:

The planets move in elliptical orbits around the sun, with the sun at one of the two foci of the elliptical orbit.
i.e. Planets revolve around sun in an orbit.The orbit of a planet around sun is an ellipse and not exact circle. Ellipse is a geometrical figure like an elongated circle.An elliptical path has two foci and sun is located at one of the foci of the ellipse and is not at the centre.
 
 


Kepler's Second law:

Each planet revolve around the sun in such a way that the line joining the planets to the sun sweeps out equal areas in equal intervals of time. As the line joining planets and sun sweeps equal areas in equal interval of time ,a planet moves faster when it is closer to the sun and moves slowly when it is farther from the sun.This implies that a planet does not move with constant speed around sun. The speed is greater when the planet is nearer the sun and less when the planet is farther away from the sun.

Kepler's Third law:

The cube of the mean distance of a planet from the sun is directly proportional to the square of time it takes to move around the sun.
 
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Kepler’s laws are applicable to all planets in the solar system.
 
2. When a body is dropped from some height , a uniform acceleration is produced in it by the gravitational pull of earth and this acceleration does not depend upon the mass of the falling object.So when a body is dropped freely, it falls with an acceleration of 9.8 m/s2 .Hence the acceleration of the rubber ball and metal ball when dropped from the top of a buiding will be 9.8m/s2.The acceleration produced in the freely falling bodies is same for all the bodies and it does not depend on the mass of the falling body.
Answered by Jyothi Nair | 27 Aug, 2014, 09:18: AM

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