A laser beam has intensity `4.0xx10^14Wm^-2`. Find the amplitudes of electric and magnetic fields in the beam.

Answer

`5.5xx10^8Vm^-1 ; 1.83T`

Explanation

Here, `I=4.0xx10^(14)Wm^-2`
Intensity of plane em wave is
`I=u_(av)c=1/2in_0E_0^2c`
Amplitude of electric field,
`E_0=sqrt((2I)/(in_0c))=sqrt((2xx4xx10^(14))/((8.85xx10^(-12))xx(3xx10^8))`
`5.5xx10^8Vm^-1`
Amplitude of magnetic field,
`B_0=(E_0)/c=(5.5xx10^8)/(3xx10^8)=1.83T`