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प्रश्न
Show that gravity decreases at higher altitudes.
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उत्तर
We know that the law of gravitation is
F = G ( m1 x m2)/R2
Here the F is the force due to attraction and this force is equal to the weight of the body m2g.
So m2g = G ( m1 x m2)/R2
g= (G x m2)/R2.
Here R is the distance between the earth centre and the object centre. Now if we go on higher altitude say ‘H’ then this R would increase to (R + H)
And the value of gravity at height H becomes
g’= (G x m2)/( R + H)2.
As denominator increases so g’ would be less than g and hence we can say that gravity decreases at higher altitudes.
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