An electric field in an e.m.wave is given by `E=200 sin .(2pi)/lambda(ct-x)NC^-1`. Find the energy contained in a cylinder of crossection `20 cm^2` and length 40 cm along the x-axis.

An electric field in an e.m.wave is given by `E=200 sin .(2pi)/lambda(

1.	An electric field in an e.m.wave is given by `E=200 sin .(2pi)/lambda(ct-x)NC^-1`. Find the energy contained in a cylinder of crossection `20 cm^2` and length 40 cm along the x-axis.
Answer» Correct Answer - `1.42xx10^(-10)J` Here, `E_0=200NC^-1`, `A=20cm^2=20xx10^-4m^2 , l=0.40m` Volume of cylinder, `V=Al=(20xx10^-4)xx0.40` `=8xx10^-4m^2` Energy contained in cylunder is U=volume x energy density `=Vxx1/2in_0E_0^2` `=(8xx10^-4)xx1/2xx(8.85xx10^-12)xx(200)^2` `=1.42xx10^(-10)J`

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An electric field in an e.m.wave is given by `E=200 sin .(2pi)/lambda(ct-x)NC^-1`. Find the energy contained in a cylinder of crossection `20 cm^2` and length 40 cm along the x-axis.

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