Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
Home  >>  JEEMAIN and AIPMT  >>  Physics  >>  Class12  >>  Atoms
0 votes

Sun gives light at rate of $\;1400 Wm^{-2}\;$ of area perpendicular to direction of light . Assume $\;\lambda\;$ (sun light )= $\;6000 A^{0}\;.$ Then no.of Photons/sec arriving at $\;1m^2\;$ area at that part of earth is


Can you answer this question?

1 Answer

0 votes
Answer : (b) $\;4.2\times10^{22}$
Explanation :
$\varepsilon =\;$ energy of photon =$ h \nu=\large\frac{hC}{\lambda} \quad \; (C=3\times10^{8} m/s) $
Let n be no . of photon received/sec per unit area
$\eta=\large\frac{IA}{\large\frac{\varepsilon}{energy of photon}}=\large\frac{(1400\times1)\times(6000\times10^{-10})}{6.6\times10^{-34}\times3\times10^{8}}$


answered Feb 21, 2014 by yamini.v
edited Nov 11, 2014 by thagee.vedartham

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, AIPMT Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App