Light wave traveling in air along x -direction is given by E _{ y }=540 sin π × 10^{4}( x - ct ) V

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8.Electromagnetic waves

easy

Light wave traveling in air along $x$-direction is given by $E _{ y }=540 \sin \pi \times 10^{4}( x - ct ) Vm ^{-1}$. Then, the peak value of magnetic field of wave will be $\dots \times 10^{-7}\,T$ (Given $c =3 \times 10^{8}\,ms ^{-1}$ )

A

$18$

B

$54$

C

$5.4$

D

$1.8$

(JEE MAIN-2022)

Solution

$E _{ y }=540 \sin \pi \times 10^{4}( x – ct ) Vm ^{-1}$

$E _{0}=540\,Vm ^{-1}$

$B _{0}=\frac{ E _{0}}{ C }=\frac{540}{3 \times 10^{8}}=18 \times 10^{-7}\,T$

Standard 12

Physics

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