The energy of a photon is `3 xx10^(-12)erg`.What is its wavelength in nm?`(h=6.62xx10^(-27)erg-s,3xx10^(10)cm s^(-1))`

Options

A. 662
B. 1324
C. 66.2
D. 6.62

Answer

a

Explanation

The energy of photon, `E=3xx 10^(-12)erg`
Planck.s constant.\,`h=6.62xx10^(-27)erg`
velocity of light,`c=3xx10^(10) cms^(*1)`
acccording tp planck.s quantum theory,
`E=hv=(hc)/lambda (therefore c=vlambda)`
`3xx10^(-12)=(6.62xx10^(-27)xx3xx10^(10))/lambda`
`implies lambda=3xx10^(-12)=(6.62xx10^(-27)xx3xx10^(10))/(3xx10^(-2))`
`=662xx10^(-7)cm`
=`662xx10^(*9)`
`=662nm`