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What is the wavelength (in nm) of a single photon with an energy of 2.05 eV?

a) 450 nm

b) 550 nm

c) 650 nm

d) 750 nm

User Nilinswap
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1 Answer

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Final answer:

To calculate the wavelength of a photon with an energy of 2.05 eV, we use the energy-wavelength relationship with Planck's constant and the speed of light. After converting eV to joules and substituting the values into the formula, we find a wavelength of approximately 603.94 nm, making the closest answer (c) 650 nm.

Step-by-step explanation:

To find the wavelength of a single photon given its energy, you can use the formula that relates a photon's energy (E) to its wavelength (λ) through Planck's constant (h) and the speed of light (c):

E = (h * c) / λ

First, we need to convert the energy from electron volts to joules since Planck's constant is given in joules·seconds. The conversion factor is 1 eV = 1.602 x 10-19 J. Thus, an energy of 2.05 eV is equivalent to 2.05 * 1.602 x 10-19 J. Next, using Planck's constant (h = 6.626 x 10-34 js) and the speed of light (c = 3.00 x 108 m/s), we can rearrange the formula to solve for λ:

λ = (h * c) / E

Substituting the values, we find the wavelength:

λ = (6.626 x 10-34 js * 3.00 x 108 m/s) / (2.05 * 1.602 x 10-19 J) = 603.94 nm.

User Ganesh H
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