why can ships travel faster in cold water than in warm water?

Answer 1

I don't think the reasons above affect the perfornamce of ships very much. The density of sea water does not vary very much.

Property of sea water here: http://www.chrismanual.com/Intro/prop.htm

The viscosity (bigger viscosity means harder to stir) of sea water decrease with temperature rise. So at cold temp, more friction will be between the ships hull and sea water, this will make the ship run slower.

I can think of one factor that will contribute to the better performance of ships at low temp. Ships use sea water to serve as the low temperature heat sink. Thermodynamically, the lower the heat sink temp the greater will be the effciency of the engine. So at lower cold sea water temp the ship's engine is running at a relatively higher efficiency.

Answer 2

First, do ships really travel faster in cold water than warm? Can you provide some references to back this claim up?

Answer 3

Cold water has more liquid-type properties than warm water, since warm water is closer to the vapor state.

A ship needs buoyancy to stay afloat, and since cold water is more liquid and stable than warm water, the ship will go through it faster.

Answer 4

In cold water the ship will sink less as the density cold water is higher than that of warm water.So the portion of ship in contact with water will be less and so the friction will be less as friction is directly proportional to area of contact.Hence the phenomenon

Answer 5

Cold water is denser than warm, so the ship rides higher in cold, and there's less friction.

Answer 6

so they can get to the warm water and out of the cold

Answer 7

colder water is denser than warm water.
hence when the propellers rotate in cold water, more thrust is generated than in warm water, allowing the ship to go faster

Answer 8

i dont think it has something to do with the density of water....did you ever tried to do an experiment with the following considerations>
power
speed
temp
weight