The number of photons emitted by a monochromatic (single frequency) infrared range finder of power 1 β JEE Mains Chemistry Past Papers Chemistry Question
Question
The number of photons emitted by a monochromatic (single frequency) infrared range finder of power 1 mW and wavelength of 1000 nm, in 0.1 second is x Γ 1013. The value of x is _________. (Nearest integer) (h = 6.63 Γ 10β34 Js, c = 3.00 Γ 108 msβ1) 1 mW rFkk 1000 nm rjaxnS/;Z ds ,d o.khZ (,dy vko`fΓk) vojDr ijklekih ls 0.1 lsdsUM esa mRlftZr QksVkWuksa dh la[;k x Γ 1013 gSA x dk eku gS_________. (fudVre iw.kkΒ±d esa) (h = 6.63 Γ 10β34 Js, c = 3.00 Γ 108 msβ1)
π‘ Solution & Explanation
Energy emitted in 0.1 sec s J . sec . 3 ο ο΄ ο½ = 10-4 J If 'n' photons of ο¬ = 1000 nm are emitted, then 10β4 = ο¬ ο½hc n οο 10β4 = 8 10 10 10 . n ο ο ο΄ ο΄ ο΄ ο΄ ο΄ οο n = 5.02 Γ1014 = 50.2 Γ1013 οο 50 (nearest integer)