Two identical research vessels, each of mass 6.4×104 tonnes6.4 \times 10^4\text{ tonnes}6.4×104 tonnes, are docked parallel to one another in a harbour. The distance between their centres of mass is 32 m.
What is the magnitude of the gravitational force of attraction between the two vessels?
2.7×10−4 N2.7 \times 10^{-4}\text{ N}2.7×10−4 N
4.2×10−6 N4.2 \times 10^{-6}\text{ N}4.2×10−6 N
2.7×102 N2.7 \times 10^2\text{ N}2.7×102 N
8.5×103 N8.5 \times 10^3\text{ N}8.5×103 N
