Answer:
a
[tex]E = 4.0733 *10^{-19} \ J [/tex]
b
[tex]n = 2.45 *10^{16} [/tex]
c
tex]k = 2.45 *10^{19} \ photon / second[/tex]
Explanation:
From the question we are told that
The wavelength is [tex]\lambda = 488 \ nm = 488*10^{-9} \ m[/tex]
The power is [tex]P = 100 \ mW = 100 *10^{-3} \ W[/tex]
The diameter of the circle is [tex]d = 5 \mu m = 5.0*10^{-6}\ m[/tex]
The time taken is [tex]t = 10 \ s[/tex]
Generally the energy of the photon is mathematically represented as
[tex]E = \frac{hc }{\lambda}[/tex]
substituting [tex] 6.626*10^{-34} \ J\cdot s [/tex] for h , [tex]3.0*10^8 \ m/s[/tex] for c
So
[tex]E = \frac{ 6.626 *10^{-34} * 3*10^8 }{488 *10^{-9}}[/tex]
=> [tex]E = 4.0733 *10^{-19} \ J [/tex]
Generally the number of photons emitted is mathematically
[tex]n = \frac{P}{E}[/tex]
[tex]n = \frac{10 *10^{-3}}{4.07733 *10^{-19}}[/tex]
[tex]n = 2.45 *10^{16} [/tex]
Generally the number of photons emitted in by the laser in ten seconds is mathematically
[tex]k = \frac{10}{E}[/tex]
=> [tex]k = \frac{10}{4.0733 *10^{-19}}[/tex]
=> [tex]k = 2.45 *10^{19} \ photon / second[/tex]
