Advertisements
Advertisements
Question
Show that gravity decreases at higher altitudes.
Advertisements
Solution
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.
APPEARS IN
RELATED QUESTIONS
What happens to the force between two objects, if the mass of one object is doubled?
At noon, the sun and the earth pull the objects on the earth's surface in opposite directions. At midnight, the sun and the earth pull these objects in same direction. Is the weight of an object, as measured by a spring balance on the earth's surface, more at midnight as compared to its weight at noon?
Three equal masses m are placed at the three corners of an equilateral triangle of side a. Find the force exerted by this system on another particle of mass m placed at (a) the mid-point of a side, (b) at the centre of the triangle.
Write an expression for the gravitational force of attraction between two bodies of masses m1 and m2 separated by a distance r.
A ball is thrown vertically upwards. It goes to a height 20 m and then returns to the ground. Taking acceleration due to gravity g to be 10 ms-2 , find :
the total time of journey of the ball .
How will the force of gravitation between two objects change if the distance between them is:
Halved
Is the law of gravitation applicable in case of the sun and the moon?
What is meant by the equation :
`g= Gxxm/r^2`
where the symbols have their usual meanings.
At what height above the earth's surface would the value of acceleration due to gravity be half of what it is on the surface? Take the radius of earth to be R.
Name and state the action and reaction in the following case:
Hammering a nail.
