Why is the sea blue and when you take a cup full in your hands its clear???

Question

Why is the sea blue and when you take a cup full in your hands its clear???

Answer 1

the sea is blue because water is blue !! it seems crazy as we have all been brought up to believe that water is blue because it reflects the sky but that is not true. if that was the case it would be white when the sky is full of clouds (from wikipedia). it's just that water is a very pale blue (so pale that when you have a small amount in your hands you don't notice).  

Answer 2

Because the sea reflects the colour of the sky, making it blue, but when you lift it, it's not deep enough to reflect properly and so it just shows your hands underneath.

Answer 3

The blue is a reflection of the sky.  but when you lift it it's not deep enough to reflect in its  intended way

Answer 4

cus its in alusian .. i dont no

Answer 5

There are two reasons for the color of the sea; both of them contribute to the answer.

A. The sea reflects the sky.

You have probably noticed that the sea is not very blue-looking when the sky is overcast. Water reflects and scatters the light that strikes it; this is shown by the fact that you can see your reflection in puddles. When the sky is brilliant blue, the sea is also, because it reflects the blue of the sky. A good answer to why the sky is blue has already been posted at MADSci.

B. The sea refracts light just as the sky does.

Blue light is more easily bent, or refracted, than red light; thus, light refracted back from the surface of the sea appears blue. Furthermore, when you are underwater the water around you appears blue because more blue light is scattered back to your eye than red light. Here are some professional shots to show what I mean.

that's it!..=)