The electromagnetic force, and the gravitational force<span>.
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It's called buoyancy. It is the tendency of an object to float
The refractive index of water is

. This means that the speed of the light in the water is:

The relationship between frequency f and wavelength

of a wave is given by:

where v is the speed of the wave in the medium. The frequency of the light does not change when it moves from one medium to the other one, so we can compute the ratio between the wavelength of the light in water

to that in air

as

where v is the speed of light in water and c is the speed of light in air. Re-arranging this formula and by using

, we find

which is the wavelength of light in water.
Answer:
A hygroscopic substance is one that readily attracts water from its surroundings, through either absorption or adsorption.
Explanation:
A hygroscopic substance is one that readily attracts water from its surroundings, through either absorption or adsorption.