Question

How many photons of light having a wave length of 5000Å are necessary to provide 1 joule of energy ?​

Answer 1

Answer:

$e = \frac{nhc}{wavelength}$

$= > n = \frac{e \times wavelenth}{hc}$

$= > \frac{1 \times 5000 \times {10}^{ - 10} }{6.626 \times {10}^{ - 34} \times 3 \times {10}^{8} }$

$= > 2.5 \times {10}^{18}photons$

Answer 2

Answer:

E=hu=hc/wavelength = 6.626×10^-34×3×10^8/(5000×10^-10)= 3.976×10^-19 joule per photon