Two particles are placed at some distance. If the mass of each of the two particles is doubled, keeping the distance between them unchanged, the value of gravitational force between them will be (a) 1 4 (b) 4 times (c) 1 2 times (d) unchanged

(B) 4 times
As the gravitational force is directly proportional to the product of masses to the two objects, and we are doubling the mass of both the objects i.e. the original gravitational force *2*2 i.e. *4 .
Therefore it will be force times the original one.

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