8.Electromagnetic waves
medium

$I (watts/m^2)$ તીવ્રતા ધરાવતા વિદ્યુતચુંબકીય તરંગ દ્વારા સંપૂર્ણ અપરાવર્તક સપાટી પર કેટલું દબાણ લાગે?

A

$ Ic $

B

$ I{c^2} $

C

$ I/c $

D

$ I/{c^2} $

Solution

(c) Momentum of a photon

$=\frac{h}{\lambda}=\frac{h}{c / v}=\frac{h v}{c}=\frac{E}{c}$

Momentum over unit area

$=\frac{E}{A c}=\frac{I}{c}\left[I=\frac{E}{A} \text { for wave }\right]$

since surface is non reflecting, final momentum of photon $= 0,$ change in momentum $=\frac{I}{c}$

So, force per unit area $=\frac{I}{c}$

Pressure of radiation $=\frac{I}{c}$

Standard 12
Physics

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.