science question

Will a magnetic field be part of the experiment?

No, why do you ask about a magnetic field?

It's called a thermosyphon--the hot water expands becomes less dense and rises displacing the cooler water at the top which being less dense sinks---As long as the heat sink is above the heat source you'll form a thermosyphon----Warning you want to provide an expansion volume when you do this experiment---if you seal the copper ring and fill it completely full of liquid water heating will result in single phase expansion until the copper ring containment ruptures potentially violently (this is known as hydraulic rupture and is the reason for fill limits on propane storage tanks).

Historical note--the cooling systems on Model T Fords used a thermosyphon, The engine (the heat source) is lower than the radiator--consequently there was no need for water pumps on Model T cooling systems.

Rap

Rap's got the real smarts...

I couldn't agree with you more rap.

You are saying warm water is less dense and it rises as a result, but then ice is also less dense and floats on top of water. This is more evident in the polar regions where polar bears can walk on top of ice with water underneath (it is also essential in maintaining aquatic life during frozen periods).

So warm water is less dense than cold, ice is also less dense than water. Shed some light, what is the critical temperature that determines which one of the 2 rises?

Water is somewhat unique in that it's density increases down to about 4DegC and increases slightly as it cools to freezing (0 DegC), so that it's solid density is less than the liquid density--that's why ice floats in liquid water. The polar ice floats have another factor--sea water is salty and the ice is pure--and salty water is more dense than pure water--but that's another subject.

Try this experiment with melted paraffin (candle wax). Melt some paraffin in a clear glass and let it cool to a solid. When the paraffin is at equilibrium (solid and liquids) where does the solid forms?--It will be on the bottom indicating that the solid is denser than the liquid (that is the usual case). Water in the same condition freezes to ice on the top indicating that the solid is less dense than the liquid.

The reason for water's strange behavior is called hydrogen bonding. It's the result of a physical affinity between the relatively proton rich arms of the hydrogen atoms and the electron rich portion of the oxygen atom of the H2O molecule (negatives attract). Hydrogen bonding is also the reason for snowflakes being hexagonal crystals.

Rap

Short answer - yes, there will be heat exchanged so it will create a turbulent flow in the water.

Convection

rap knows what he's talking about except that the second "increase" should be "decrease", but that was probably a typo.

Interesting the Ford model T didnt use a water pump. I presume the power output of later engines was such that relying on thermosyphon was not sufficient cooling. Domestic heating systems exploited the same phenomenon.