THE BASIC PRINCIPLES OF ILLUMINATIONS

refers to the number of entire wavelengths that go by a offered point in Area every second; the SI unit for frequency is Hertz (Hz)‍ , which is such as “per seconds” (‍ prepared as 1s‍  or s−one)‍ .Light moves in a straight line. The straight line path is usually drawn for a ray. Humans can only see rays of light traveling immedia