Select the correct answer.

If the approximate energy of a photon present in an X-ray is [tex]$8.0 \times 10^{-15}$[/tex] joules, what's the frequency of the X-ray? Given: Planck's constant is [tex]$6.63 \times 10^{-34}$[/tex] joule seconds.

A. [tex][tex]$1.2 \times 10^{14}$[/tex][/tex] hertz
B. [tex]$1.2 \times 10^{19}$[/tex] hertz
C. [tex]$8.2 \times 10^{18}$[/tex] hertz
D. [tex][tex]$8.3 \times 10^{19}$[/tex][/tex] hertz



Answer :

To determine the frequency of an X-ray photon given its energy, we employ the relationship between energy (E), Planck's constant (h), and frequency (f). This relationship is expressed by the formula:

[tex]\[ E = h \cdot f \][/tex]

Here:
- [tex]\( E \)[/tex] is the energy of the photon.
- [tex]\( h \)[/tex] is Planck's constant.
- [tex]\( f \)[/tex] is the frequency we need to find.

We can rearrange this formula to solve for the frequency (f):

[tex]\[ f = \frac{E}{h} \][/tex]

Given:
- The energy of the photon ([tex]\( E \)[/tex]) is [tex]\( 8.0 \times 10^{-15} \)[/tex] joules.
- Planck's constant ([tex]\( h \)[/tex]) is [tex]\( 6.63 \times 10^{-34} \)[/tex] joule seconds.

Substitute the given values into the formula:

[tex]\[ f = \frac{8.0 \times 10^{-15}}{6.63 \times 10^{-34}} \][/tex]

Perform the division:

[tex]\[ f = 1.206636500754148 \times 10^{19} \text{ hertz} \][/tex]

Thus, the frequency of the X-ray is approximately [tex]\( 1.2 \times 10^{19} \)[/tex] hertz.

Therefore, the correct answer is:

B. [tex]\( 1.2 \times 10^{19} \)[/tex] hertz