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1 vote
What is the energy of a photon whose frequency is 6.0 x 10^20?

(h=6.63 x10^-34 j•s; 1 eV=1.06x10^-19 J)


A. 1.6 MeV

B. 2.5 MeV

C. 3.3 MeV

D. 4.8 MeV

User Kunukn
by
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1 Answer

3 votes

Answer:

3.75 MeV

Step-by-step explanation:

The energy of the photon can be given in terms of frequency as:

E = h * f

Where h = Planck's constant

The frequency of the photon is 6 * 10^20 Hz.

The energy (in Joules) is:

E = 6.63 x10^(-34) * 6 * 10^(20)

E = 39.78 * 10^(-14) J = 3.978 * 10^(-13) J

We are given that:

1 eV = 1.06 * 10^(-19) Joules

This means that 1 Joule will be:

1 J = 1 / (1.06 * 10^(-19)

1 J = 9.434 * 10^(18) eV

=> 3.978 * 10^(-13) J = 3.978 * 10^(-13) * 9.434 * 10^(18) = 3.75 * 10^(6) eV

This is the same as 3.75 MeV.

The correct answer is not in the options, but the closest to it is option C.

User Bryce Easley
by
4.8k points