Question

Part A calculate the energy of a photon of electromagnetic radiation whose frequency is 6.78x10^12 s-1

Part B calculate the energy of a photon of radiation whose wavelength is 325 no

Part C what wavelength of radiation has photons of energy 2.81x10^-18 J

Answer 1

h = planck constant
= (6.6*10^-34) J.s
part A
energy = h*(frequency)
= (6.6*10^-34)*6.78*10^12
= (4.5*10^-21) J

part B
energy = (h*c)/(wavelength)
wavelength = 325 nm
= (325*10^-9) m
c = speed of light
= (3*10^8) m/s

energy = (6.6*10^-34*3*10^8)/(325*10^-9)
= (6.1*10^-19) J

part C
energy = (h*c)/(wavelength)
wavelength = 325 nm
= (325*10^-9) m
c = speed of light
= (3*10^8) m/s

so,
2.81*10^-18 = (6.6*10^-34*3*10^8)/(wavelength)
wavelength = (19.8*10^-26)/(2.81*10^-18)
= (7.1*10^-8) m