Why does a rainbow appear bent or arched in a semicircle in the sky? ?

Question

Why does a rainbow appear bent or arched in a semicircle in the sky? ?

Answer 1

Check out this link , it explains it better than Ic ould!

Answer 2

A rainbow just appears as an arch but it is actually a complete circle. We just don't see the whole thing because the horizon gets in the way. Sometimes people on planes will see the entire circle with the shadow of the plane in the center.

The rainbow is circular because when a raindrop bends light, the light exits the raindrop at a 40-42 degree angle away from the angle it entered the raindrop.

White light is made up of a mixture of all the different colors. Light takes the form of waves and all the different colors have a different wavelength. Red light has the longest wavelength (720 nm) while violet has the shortest (380 nm). These different wavelengths can be used to explain why you see all the different colors in the rainbow. When light hits water droplets in the air, it is bent slightly - this bending is called diffraction. The amount of diffraction depends on the wavelength - Red light is bent less than blue light so when white light meets the water droplets, it is separated into all the different colors.

If you turn on a garden hose, adjust the nozzle to a fine spray and stand with your back to the sun, you will see a rainbow shining in the spray!

Answer 3

With the sun behind you (generally), you will see the colors of the spectrum at a narrow range of angles.  The solution to the geometry problem..."What is the locus of points (shape) in space that are equi-angular from a given point"" is a cone sliced perpendicular to its principle axis.  That locus is a circle.  (You can see the entire circle at altitude (in a plane, for example)...otherwise you just see part of it...an arc).

-Fred