Visible light is the small part of the electromagnetic spectrum that human eyes can detect. Different wavelengths in this range are seen as different colors.
Visible light is just the slice of electromagnetic waves our eyes happen to notice.
Showing a random 20 of 50 problems.
Example 1
challenge
In a vacuum, light A has wavelength 400 nm and light B has 600 nm. Find the ratio of their frequencies fA/fB.
Example 2
medium
A green light has λ=550nm in vacuum. Find its frequency in Hz.
Example 3
medium
A prism splits white light into colors. Why does this happen?
Example 4
easy
Which color of visible light has the shortest wavelength?
Example 5
challenge
A photon of green light has frequency 6.0×1014 Hz. Using h=6.63×10−34 J\cdotps, find its energy.
Example 6
medium
Sunlight (white) shines on a wall painted matte blue. (a) Which wavelengths reach an observer? (b) What does the wall look like under a pure red light?
Example 7
medium
A green light enters glass and slows from c to 2.0×108m/s. Find the glass's refractive index for green light.
Example 8
easy
Light with wavelength 520 nm appears what color?
Example 9
easy
True or false: increasing the brightness of a light bulb changes the wavelength of its red glow.
Example 10
medium
A light source emits photons of frequency f=4.3×1014Hz. Use h=6.63×10−34J s to find each photon's energy.
Example 11
medium
A 450 nm blue photon and a 650 nm red photon: which has the longer wavelength and lower frequency?
Example 12
easy
What part of the electromagnetic spectrum can human eyes detect?
Example 13
easy
Green light has frequency f=6.0×1014 Hz. Find its wavelength in vacuum.
Example 14
easy
What is the approximate wavelength range of visible light?
Example 15
hard
A monochromatic green source (λ0=530nm) enters a glass with ng=1.52 for green. (a) Find λ in the glass. (b) If a red component at 650 nm enters the same glass with nr=1.50, find its wavelength in the glass. (c) Which color has the larger refractive index?
Example 16
hard
A laser pointer emits at 532 nm with output power 5 mW. About how many photons per second does it emit?
Example 17
hard
A bee can see ultraviolet light at 350 nm; a human cannot. By what percentage shorter is the bee's UV than the human violet edge near 400 nm?
Example 18
challenge
Two coherent visible-light beams overlap. Beam A has wavelength 500 nm and beam B has 700 nm. State whether they can produce stable, stationary interference fringes (assume both have the same direction and equal amplitude).
Example 19
easy
Place these in order from longest wavelength to shortest: green, red, blue.
Example 20
hard
Light with vacuum wavelength 600 nm enters a transparent solid where its speed is 1.8×108m/s. Find (a) the refractive index and (b) the wavelength inside the solid.