Find the number of photons emitted per second | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) Given: Power $P = 100\, W$,Wavelength $\lambda = 694\, nm = 694 	imes 10^{-9}\, m$.Energy of one photon $E = \frac{hc}{\lambda}$.The number of ph

Vedclass · Accepted Answer

$3.49 	imes 10^{20}$

Vedclass · Answer

(A) Given: Power $P = 100\, W$,Wavelength $\lambda = 694\, nm = 694 	imes 10^{-9}\, m$.Energy of one photon $E = \frac{hc}{\lambda}$.The number of photons emitted per second $n$ is given by $n = \frac{P}{E} = \frac{P\lambda}{hc}$.Substituting the values: $h = 6.63 	imes 10^{-34}\, J\cdot s$,$c = 3 	imes 10^8\, m/s$.$n = \frac{100 	imes 694 	imes 10^{-9}}{6.63 	imes 10^{-34} 	imes 3 	imes 10^8}$.$n = \frac{69400 	imes 10^{-9}}{19.89 	imes 10^{-26}} \approx 3489.19 	imes 10^{17} \approx 3.49 	imes 10^{20}$ photons/second.

Find the number of photons emitted per second by a $100\, W$ red light source. Assume for simplicity that the average wavelength of each photon is $694\, nm$.

Similar Questions

When a photon enters glass from air,which one of the following quantities does $\underline{\text{NOT}}$ change?

Which scientist discarded the postulate of ether?

What is the energy of a photon whose wavelength is $6840\,\mathring{A}$? (in $eV$)

The number of photons emitted from a photocell by a source placed at a distance of $0.5 \ m$ is how many times the number of photons emitted by the same source placed at a distance of $1 \ m$?

$A$ radio transmitter operates at a frequency of $880 \ kHz$ and a power of $10 \ kW$. The number of photons emitted per second is .......

Vedclass Test Series

Exam Paper Generator

Online Exam Module