lesson 8

• when a beam of white light was made to pass through a prism, the beam of white light was separated into different colors
• dispersion - process by which visible light is separated into different colors due to the differences in the degrees of refraction
• red - greatest frequency and energy, shortest wavelength
• red - lowest frequency and energy, longest wavelength
• luminous intensity - measure of the brightness of the source of light
• luminous intensity is often expressed in candela (cd)
• the brighter the source of light, the greater the quantity of light energy it transmits
• illumination - the amount of light falling on a unit area of the objects surface
• illumination increases as the value of luminous intensity increases
• illumination decreases as the distance between the source and the receiving surface of the object increases
• rainbow is formed by the dispersion of sunlight in water droplets