Answer:
[tex]\lambda=1.37 fm[/tex]
Explanation:
The Planck Eistein relation, states that the energy of a photon is proportional to its frequency:
[tex]E=h\nu(1)[/tex]
h is the Plank constant.The frequency of a photon is defined as the speed of light over its wavelength:
[tex]\nu=\frac{c}{\lambda}(2)[/tex]
Replacing (2) in (1):
[tex]E=\frac{hc}{\lambda}\\\lambda=\frac{hc}{E}\\\lambda=\frac{(4.14*10^{-15}eV\cdot s)(3*10^8\frac{m}{s})}{0.91*10^{9}eV}\\\\\lambda=(1.37*10^{-15}m)*\frac{1fm}{10^{-15}m}\\\\\lambda=1.37 fm[/tex]
