Answer:
The maximum value of the magnetic field in the wave is [tex]7.79\times10^{-8}\ T.[/tex]
Explanation:
Given that,
Average value of pointing vector = 0.724 W/m²
We need to calculate the magnetic field
Using formula of pointing vector
[tex]S=\dfrac{1}{\mu_{0}}(E\times B)[/tex]
The average value of pointing vector
[tex]S=\dfrac{1}{2\mu_{0}}\times E_{0}B_{0}....(I)[/tex]
We know that,
[tex]E_{0}=cB_{0}[/tex]
Put the value of [tex]E_{0}[/tex] in equation (II)
[tex]S=\dfrac{1}{2\mu_{0}}\times c(B_{0})^2[/tex]
substitute the value in the formula
[tex]0.724=\dfrac{1}{2\times4\pi\times10^{-7}}\times3\times10^{8}\times (B_{0})^2B_{0}=\sqrt{\dfrac{0.724\times2\times4\pi\times10^{-7}}{3\times10^{8}}}B_{0}=7.79\times10^{-8}\ T[/tex]
The maximum value of the magnetic field in the wave is [tex]7.79\times10^{-8}\ T.[/tex]
