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A blackbody radiates 9.5 x 10-17J of energy per second at a wavelength of 113 nm. How

many photons are emitted per second?

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Answer:

Step-by-step explanation:

The energy of a single photon can be calculated using the Planck-Einstein relation:

E = hν

where E is the energy of the photon, h is Planck's constant (6.626 x 10^-34 J·s), and ν is the frequency of the radiation.

We can use the speed of light to convert the wavelength of 113 nm to frequency:

c = νλ

where c is the speed of light (3.00 x 10^8 m/s), λ is the wavelength in meters, and ν is the frequency.

ν = c/λ = (3.00 x 10^8 m/s)/(113 x 10^-9 m) = 2.654 x 10^15 Hz

Now we can calculate the energy of a single photon:

E = hν = (6.626 x 10^-34 J·s)(2.654 x 10^15 Hz) = 1.76 x 10^-18 J

The number of photons emitted per second can be calculated by dividing the total energy radiated by the energy of a single photon:

number of photons = (9.5 x 10^-17 J/s)/(1.76 x 10^-18 J/photon) ≈ 5.40 x 10^16 photons/s

Therefore, approximately 5.40 x 10^16 photons are emitted per second.

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