Q5 of 46 Page 249

State Newton’s law of gravitation. Write an expression for acceleration due to gravity on the surface of the earth. If the ratio of acceleration due to gravity of two heavenly bodies is 1:4 and the ratio of their radii is 1:3, what will be the ratio of their masses?

Newton’s law of gravitation states that the gravitational force between 2 objects is proportional to the product of the masses of the 2 objects and inversely proportional to the square of the distance between them.

Now


Where G is the universal gravitational constant( = 6.67 × 10-11 Nm2kg-2),


M is the mass of the earth,


R is the radius of the earth.


(given)


So,




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(i) What is the acceleration of the mass?


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ii) What will be the effect of this action on the earth?

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