Question

Calculate the frequency of a photon of energy 3eV.

Answer 1

By using this formula

E=hv

E=3ev given change its unit by multiple with 1.6*10^-19

I.e 4.8*10^-19

Put the value in the formula

h =6.6*10^-34 u will get the answer

Approximately 5*10^16

Answer 2

• Energy=E=3eV
• Frequency=v=?

we know

$\boxed{\sf E=hv}$

$\\ \sf\longmapsto v=\dfrac{E}{h}$

$\\ \sf\longmapsto v=\dfrac{3eV}{6.626\times 10^{-34}Js}$

$\\ \sf\longmapsto v=\dfrac{3(1.6\times 10^{-19}J)}{6.626\times 10^{-34}Js}$

$\\ \sf\longmapsto v=\dfrac{4.8\times 10^{-19}J}{6.626\times 10^{-34}Js}$

$\\ \sf\longmapsto v=0.724\times 10^{15}s^{-1}$

$\\ \sf\longmapsto v=7.2 \times 10^{14}s^{-1}$