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In a traveling plane electromagnetic wav...

In a traveling plane electromagnetic wave, the maximum magnetic field is `1.26xx10^(-4) T.` The intensity of the wave is (Assume `mu_(0) = 1.26 10^(-6)H//m)`

A

`1.56 xx10^(6) W//m^(2)`

B

`1.89 xx10^(6) W//m ^(2)`

C

`8.92 xx10^(5) W//m^(2)`

D

`4.62xx10^(6) W//m^(2)`

Text Solution

Verified by Experts

The correct Answer is:
B
Given,
In a travlling plane electromagnetic wave,
Maximum magnetic field, `B _(0) =1.26 xx 10 ^(-4) T`
`mu_(0) = 1.26 xx 10 ^(-6) H//m`
Intensity of wave is obtained from the equation
given by,
`I = 1/2 (B _(0) ^(2) C)/(mu_(0))`
` =1/2 ((1.26 xx 10 ^(-4)) ^(2) ( 3xx 10 ^(8)))/(1.26 xx 10 ^(-6)) `
`=1/2 xx ((1.26 ) ^(2) xx3)/( 1.26 xx 10 ^(-6))`
` = 1.89 xx 10 ^(6)`
` therefore I = 1.89 xx 10 ^(6) w//m ^(2)`
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