Answer :
Number of photons =total energy fell on leaf(E)/energy of single photon =(0.2856J/s)/3.94×10-19J =7.24×1017 photons per second
What are photons ?
In other words, photons are simply light particles. Photons are fundamental subatomic particles that carry the electromagnetic force (and so much more). The photon is the fundamental unit of electromagnetic radiation, or the "quantum." Photons are everywhere around everyone: Photons make up the light coming from the screen you're looking at, the X-rays doctors use to see bones, the radio in a car that sends out its signal, and the magnets on a fridge that support itself.
Surface area A=2.80cm2=2.80×10-4m2
Solar radiation in power P =1020W/m2
Therefore total energy falling on leaf E= P×A
E=1020×2.80×10-4=0.2856J/s
Wavelength l =504nm =504×10-9m
Energy carried by a single photon =h c/wavelength
h= plank's constant =6.626×10-34Js
c= velocity of light in vacuum =3×108m/s
Energy of single photon =6.626×10-34Js×3×108m/s/504×10-9=3.94×10-19J
- Number of photons =total energy fell on leaf(E)/energy of single photon =(0.2856J/s)/3.94×10-19J =7.24×1017 photons per second
To know about photons from the link
https://brainly.in/question/51305748
#SPJ4
