As air or water cools it?

Question

a. expands, becomes more dense and sinks

b. contracts, becomes less dense and sinks

c. contracts, becomes more dense and sinks

d. expands, becomes more dense and rises

e. expands, becomes less dense and rises

Answer 1

Is this for some kind of homework?  C is the correct answer, but it might help you to know why:

As anything cools, it loses energy (because heat is energy).  The loss of energy means that the molecules that make up the substance (whether liquid, solid, or gas) move at a slower rate.  (Yes, even solid matter has moving molecules)  The slower rate of movement basically allows the molecules to settle into each other, thus they take up less physical space.  If you have the same amout of stuff taking up less space, it is said to be more dense.

So as ANYTHING cools, it takes up less space... with the one exception being water.  As water cools, it does take up less space (becomes more dense), BUT when water freezes, it takes on a crystalline structure which actually makes it expand at it's freezing point.  After that point, the colder it gets, the smaller it gets once more.

The whole sinking or floating thing has to do with buoyancy.  To make it simple, as things become more dense, they become less buoyant.  So if you have a whole bunch of air, and some of it is cooler than the rest of it... that cool air will sink to the bottom.

In actuality, there are other factors affecting our air so that the higher you go, typically the cooler it gets.  But forget that for now.

Answer 2

wat is ur question??

As water cools Air, air contracts and becomes less dense and sinks. So " b " is the answer.

Answer 3

c