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A visible light has a wavelength of 727.3 nm. Determine its frequency, energy per photon, and color.

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3 votes

Final answer:

The frequency of the visible light with a wavelength of 727.3 nm is approximately 4.12 x 10^14 Hz. The energy per photon of this light is about 2.73 x 10^-19 J. The color of the light is red.

Step-by-step explanation:

To determine the frequency of visible light with a wavelength of 727.3 nm, we can use the formula:

c = λ * ν

where c is the speed of light (approximately 3.0 x 108 m/s), λ is the wavelength in meters, and ν is the frequency in hertz.

Converting the given wavelength of 727.3 nm to meters we get:

λ = 727.3 nm * 1 x 10-9 m/nm = 7.273 x 10-7 m

Now we can calculate the frequency:

c = 3.0 x 108 m/s = 7.273 x 10-7 m * ν

Solving for ν, we find the frequency of the visible light to be:

ν = 3.0 x 108 m/s / 7.273 x 10-7 m = 4.12 x 1014 Hz

To determine the energy per photon, we can use the formula:

E = h * ν

where E is the energy per photon in joules, h is Planck's constant (approximately 6.626 x 10-34 J⋅s), and ν is the frequency in hertz.

Substituting the calculated frequency, we get:

E = 6.626 x 10-34 J⋅s * 4.12 x 1014 Hz = 2.73 x 10-19 J

Finally, to determine the color of visible light, we can refer to the electromagnetic spectrum. Wavelengths in the range of approximately 400-700 nm are perceived as different colors by the human eye. The wavelength of 727.3 nm falls within the red portion of the spectrum, so the color of the light is red.

User Henry Mazza
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4.0k points
5 votes

Answer:


f=4.12* 10^(14)\ Hz and
E=2.73* 10^(-19)\ J

Step-by-step explanation:

The wavelength of a visible light is 727.3 nm.


727.3\ nm=727.3 * 10^(-9)\ m

The formula is as follows :


c=f\lambda

f is the frequency of the visible light


f=(c)/(\lambda)\\\\f=(3* 10^8)/(727.3 * 10^(-9))\\\\f=4.12* 10^(14)\ Hz

Energy of a photon is given by :

E = hf, h is Planck's constant


E=6.63* 10^(-34)* 4.12* 10^(14)\\\\E=2.73* 10^(-19)\ J

Red color has a frequency of
4.12* 10^(14)\ Hz and energy per photon is
2.73* 10^(-19)\ J.

User Hequ
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3.9k points