The sun emits 3x10^32J of energy every day (24 hour period). Assume it emits only yellow light (wavelength of 6X10^-7m)
A: Based on this wavelength, what is the frequency?
My answer: : (3x10^8 m/s) / (6x10^-7m) = 5x10^14 Hz
B: Based on this frequency, what is the energy of each photon of yellow light?
My answer:B: (3x10^8 m/s) (6.6x10^-34 j/h) / (6x10^-7m) = 3.3x10^-19 J ???
C: Based on this result and the suns output (3x10^32J), how many photons does the sun emit every day?
My guess at an answer: C: (3x10^32J) / (3.3x10^-19J) = 9x10^50??? Any help would be good as I think I am close to an answer.
Thank you!
A: Based on this wavelength, what is the frequency?
My answer: : (3x10^8 m/s) / (6x10^-7m) = 5x10^14 Hz
B: Based on this frequency, what is the energy of each photon of yellow light?
My answer:B: (3x10^8 m/s) (6.6x10^-34 j/h) / (6x10^-7m) = 3.3x10^-19 J ???
C: Based on this result and the suns output (3x10^32J), how many photons does the sun emit every day?
My guess at an answer: C: (3x10^32J) / (3.3x10^-19J) = 9x10^50??? Any help would be good as I think I am close to an answer.
Thank you!
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You answers look good, though the correct unit for Planck's constant is Js.
Note the 'quick' formula for photon energy is E = hf.
One way to check your logic is to make up 'easy figures'. So, if the sun's output were 200J/day and a photon carried 5J, it's easy to see this gives 40 photons/day - the operation is then clear - divide the sun's output by photon energy.
Note the 'quick' formula for photon energy is E = hf.
One way to check your logic is to make up 'easy figures'. So, if the sun's output were 200J/day and a photon carried 5J, it's easy to see this gives 40 photons/day - the operation is then clear - divide the sun's output by photon energy.
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B. Energy = Planck's constant * frequency = (6.6x10^-34) * 5x10^14
Number of photons/second = total energy / energy of 1 photon
Number of photons/second = total energy / energy of 1 photon