Question

What is the energy of a photon emitted with a wavelength of 571 nm?

Answer 1

e=h * nu, where nu is frequency of the wave.
frequency = 1/wavelength = 1/571 *10 ^-9 = 1.7 * 10^7.

e= 6.63 *10^-34 *1.7 *10^7

e=11.271 * 10^-27 Joules