Answer: The force is 6.25 times stronger.
Step-by-step explanation:
The formula to find the force of attraction between any two object is given by :-
[tex]F=G\dfrac{Mm}{d^2}[/tex] (i)
, where M and m are the masses of the objects , d is the distance between them and G is gravitational constant.
If you decrease the distance between two celestial objects by a factor of 2.5, then , the new distance will become
[tex]d'=\dfrac{1}{2.5}d[/tex]
Plug this in the above formula , we get
[tex]F'=G\dfrac{Mm}{(\dfrac{1}{2.5}d)^2}\\\\\Rightarrow\ F'=(2.5)^2(G\dfrac{Mm}{d^2})\\\\\Rightarrow\ F'=6.25(G\dfrac{Mm}{d^2})=6.25F----------\text{from }(i)[/tex]
Hence, the force is 6.25 times stronger.