Question

Why two ships traveling in parallel directions gets attracted?

Answer 1

When two boats move in parallel directions close to each other,the stream of water between the boats is set into vigorous

motion.

According to Bernoulli's theorem,when velocity of liquid flow increases the pressure decreases.Therefore the pressure exerted by water in between the boats becomes less than the pressure of water outside the boats.Due to this pressure difference both the boats are attracted towards each other.