Three light-emitting diodes (LEDs) in an electronics kit have advertised peak emission frequencies of
• 4.62×1014Hz
• 5.20×1014Hz
• 6.88×1014Hz
Assume the LEDs emit narrowly around their peak frequencies. The speed of light in air may be taken as 3.00×108ms−1. Neglect any dispersion effects.
(a) Calculate the corresponding peak wavelength for each LED in nanometers.
(b) For each LED, identify the approximate color perceived by a human observer.
(c) Rank the three LEDs from lowest to highest photon energy and relate this ranking to your wavelength or color determinations from parts (a) and (b).