Question

( quad+frac{1}{n}=frac{n}{m c} )
[
begin{array}{l}m=frac{n}{1 c} m=frac{6 cdot 63 times 10^{-28}}{5890 times 10^{-8} times 3 times 10^{10}} =3 cdot 752 times 10^{-33} 9end{array}
]

# Example 39. What is the mass of a photon of sodium light with a wavelength of 5890 Å? (h = 6.63 x 10-27 erg-sec, c = 3 x 10 cm/sec)

Solution