External force.
Air resistance, friction, grass rubbing on a rolling ball, etc.
If there is no external force on a moving object, it keeps going.
Forever !
The correct answer is refraction.
Selective breeding. That is, breeding which uses extreme selectivity
I believe it is Acoustics, the real name for it would be like Reverberation. But go with Acoustics. :)
Answer:
It is not a property of light. It is your eyes and brain.
Specifically, the three kinds of cone cells in our eye that are sensitive to different ranges of the electromagnetic spectrum. The fact that there are three means that color is three dimensional, and is the reason the pure colors form a circle even though the spectrum of wavelengths is linear.
Visible light is part of the electromagnetic spectrum; light waves of different frequencies and wavelengths are distinguished as colors by the human eye. A prism can separate the colors of white light (dispersion) because different frequencies of light have different refractive indices for a given material.
