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Find the energy of a photon with a wavelength of 820. nm?

User Sch
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1 Answer

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Answer: The energy of a photon with a wavelength of 820 nm is
2.42 * 10^(-19) m.

Step-by-step explanation:

Given : Wavelength = 820 nm

Convert nm into meter as follows.


1 nm = 10^(-9)\\So, 820 nm = 820 nm * (10^(-9) nm)/(1 nm)\\= 820 * 10^(-9) m

The relation between energy and wavelength is as follows.


E = (hc)/(\lambda)

where,

E = energy

h = Planck's constant =
6.63 * 10^(-34) kg m^(2)/s

c = speed of light =
3.0 * 10^(8) m/s


\lambda = wavelength

Substitute the values into above formula as follows.


E = (hc)/(\lambda)\\= (6.63 * 10^(-34) kg m^(2)/s * 3.0 * 10^(8) m/s)/(820 * 10^(-9) m)\\= (1.989 * 10^(-25))/(820 * 10^(-9))\\= 2.42 * 10^(-19) m

Thus, we can conclude that energy of a photon with a wavelength of 820 nm is
2.42 * 10^(-19) m.

User JibinNajeeb
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