The gravitational force between two objects is 2000 N. The mass of each object is reduced to one-third of its original mass.

To keep the gravitational force at 2000 N, use F = Gm₁m₂/r². Reducing each mass to one-third makes their mass product 1/9 of its original value, so the distance must also be reduced to 1/3 to keep the force unchanged. Therefore, the distance must be one-third the original distance.

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