A dental X-ray typically affects 194 g of tissue and delivers about 3.6 μJ of energy using X-rays that have wavelengths of 0.033 nm. What is the energy E photon , in electron volts, of X-ray photons? E photon = eV How many photons are absorbed during the dental X-ray? Assume the body absorbs all of the incident X-rays. number of photons absorbed: photons/s

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Answer:

The energy of a single photon is [tex]x= 37670.46eV[/tex]

The number of photon absorbed is [tex]z = 5.98*10^{8} \ photons[/tex]

Explanation:

From the question we are told that

       The mass of  tissue affected is  [tex]m = 194g = \frac{194}{1000} = 0.194kg[/tex]

        The energy realesed is [tex]E = 3.6 \mu J = 3.6 *10^{-6} J[/tex]

       The wavelength is [tex]\lambda = 0.033nm = 0.033 *10^{-9}m[/tex]

Generally the energy of a sigle photon is mathematically rpresented as

                   [tex]E = \frac{hc}{\lambda }[/tex]

  Where h is the Planck constant with a value of   [tex]h =6.63*10^{-34} J \cdot s[/tex]

            Substituting values

                     [tex]E = \frac{6.63*10^{-34}(3*10^8)}{0.033*10^{-9}}[/tex]

                        [tex]= 6.0272 *10^{-15}J[/tex]

  Now  

            [tex]1 eV -------> 1.60*10^{-19}J[/tex]

     

            [tex]xeV ---------> 6.02*10^{-15}J[/tex]

Making x the subject of the  formula

          [tex]x = \frac{6.02 *10^{-15}}{1.6 *10^{-19}}[/tex]

              [tex]x= 37670.46eV[/tex]

The the number of photon absorbed  is

     [tex]z = \frac{The \ energy \ deliverd \ by \ to \ tissue }{The \ energy \ of \ a \ single \ photon}[/tex]

         [tex]= \frac{3.6 *10^{-6}}{6.02*10^{-15}}[/tex]

   [tex]z = 5.98*10^{8} \ photons[/tex]

The energy of the photon in eV is gotten as; E = 37599.3 eV

The number of photons absorbed during the dental x-ray is; n = 5.976 × 10^(8) photons

We are given;

Mass of the affected tissue; m = 194 g = 0.194 kg

Energy delivered by dental x-ray; E = 3.6 μJ = 3.6 × 10^(-6) J

Wavelength; λ = 0.033 nm = 0.033 × 10^(-9) m

Formula for energy of a photon is given as;

E = hc/λ

Where;

h is Planck's constant = 6.626 × 10^(-34) J.s

c is speed of light = 3 × 10^(8) m/s

Thus;

E = (6.626 × 10^(-34) × 3 × 10^(8))/(0.033 × 10^(-9))

E = 6.0236 × 10^(-15) J

Now, let's convert the energy to eV.

From conversion calculator online, we have;

E = 37599.31 eV

Now, to get the number of photons absorbed during the dental x-ray, we will use the formula;

n = (energy delivered by dental x-ray)/(energy delivered to a single photon)

Thus;

n = (3.6 × 10^(-6))/(6.0236 × 10^(-15))

n = 5.976 × 10^(8) photons

Read more about energy of photons at; https://brainly.com/question/17227537