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CBSE Class 9 Answered

Plz can anyone explain me gravitation   
Asked by sbhangade096 | 11 Aug, 2019, 09:44: PM
answered-by-expert Expert Answer
Every massive object attracts another massive object in universe.
The massive objects may be planets, people, atoms or anything.
 
Newton formulated that the force of attraction between the massive objects is directly proportional
to their masses and inversely proportional to the distance between them.
 
If M1 and M2 are the masses of two objects which are at a distance R from each other,
then the gravitational attractive force F between them is given by
 
begin mathsize 12px style F space equals space G cross times fraction numerator M subscript 1 cross times M subscript 2 over denominator R squared end fraction space space................ left parenthesis 1 right parenthesis end style
where G is universal gravitational constant and its value in SI units is 6.672×10-11 N m2 kg-2
 
We are seeing on earth, everything above the earth surface falls towards earth. This is due to
the gravitational force of attraction between earth and the falling object.
 
If m is the mass of falling object, M is mass of earth and R is earth radius then as per eqn.(1)
 
we get Gravitational force, F = G× m×M/R2 ...................(2)
 
since acceleration = F/m,  we get acceleration g due to gravity as,  g = G×M/R2 ......................(3)
 
If we substitute the values for mass of earth and radius of earth in eqn.(3), we get g = 9.8 m/s2
Answered by Thiyagarajan K | 12 Aug, 2019, 06:59: AM

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