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Physics Help! ?
Light is shining perpendicularly on the surface of the earth with an intensity of 680 W/m2. Assuming that all the photons in the light have the same wavelength (in vacuum) of 585 nm, determine the number of photons per second per square meter that reach the earth.
N =
1 Answer
- ?Lv 77 hours ago
For each photon, E = hc/λ
E = 6.626e-34kg·m²/s * 3e8m/s / 585e-9m = 3.4e-19 J
N = (I / E) * 1m² * 1s = (680W/m² / 3.4e-19J) * 1m² * 1s
N = 2.00e21 photons
