Question

two point masses m and 3m are placed at a distance L opart another point mass is placed in between on the line joining them so that the net gravitational force acting onit due to masses m and 3M is zero

Answer 1

distance between M and m =x

GMm/x^2=G3Mm/(L-x)^2

now by solving above equation

L-x=√3x

x=L/1+√3

now by the formula of force between two masses

F=GMm/x^2

plug in the value of"x" in it  

F=GMm/(L/√3+1)^2

F=[GMm(√3+1)^2]/L^2.

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