1. [tex]5.94\cdot 10^{14} Hz[/tex]
The frequency of a photon is given by:
[tex]f=\frac{c}{\lambda}[/tex]
where
c is the speed of light
[tex]\lambda[/tex] is the wavelength
The wavelength of the photon in this problem is
[tex]\lambda=505 nm=5.05\cdot 10^{-7}m[/tex]
So, the frequency of the photon is
[tex]f=\frac{3\cdot 10^8 m/s}{5.05\cdot 10^{-7} m}=5.94\cdot 10^{14} Hz[/tex]
2. [tex]3.94\cdot 10^{-19}J, 2.46 eV[/tex]
The energy of a photon is given by
[tex]E=hf[/tex]
where
h is the Planck constant
f is the frequency of the photon
The frequency of the photon in this problem is
[tex]f=5.94\cdot 10^{14} Hz[/tex]
so its energy in Joules is
[tex]E=(6.63\cdot 10^{-34}Js)(5.94\cdot 10^{14}Hz)=3.94\cdot 10^{-19}J[/tex]
And since
[tex]1 eV = 1.6\cdot 10^{-19}J[/tex]
The energy in eV is
[tex]E=\frac{3.94\cdot 10^{-19} J}{1.6\cdot 10^{-19}J/eV}=2.46 eV[/tex]
