The oscillating electric field in a plane electromagnetic wave is given by [tex]{50\sin (\omega t-kx) V/m}[/tex], and the frequency of electric field is 2 × 10⁷ Hz. Find: (a) Find [tex]{\omega}[/tex], [tex]{\lambda}[/tex], k and write the expression for the electric field (b) Find [tex]{B_{0}}[/tex] and write the expression for magnetic field (c) Predict the Direction of propagation of electromagnetic wave.​

Respuesta :

Here, we are given with:

[tex]{:\implies \quad \longrightarrow \begin{cases}\sf E_{0}= 50\: V/m\\ \sf \nu = 2\times 10^{7}Hz\end{cases}}[/tex]

(a) So now, we can thus obtain

[tex]{:\implies \quad \sf \omega =2\pi \nu}[/tex]

[tex]{:\implies \quad \sf \omega =2\pi (2\times 10^{7})}[/tex]

[tex]{:\implies \quad \boxed{\bf{\omega = 4\pi \times 10^{7}\: s^{-1}}}}[/tex]

Now, finding [tex]\lambda[/tex]

[tex]{:\implies \quad \sf \lambda =\dfrac{c}{\omega}=\dfrac{3\times 10^{8}}{4\pi \times 10^{7}}}[/tex]

[tex]{:\implies \quad \boxed{\bf{\lambda \approx 2.39\:m}}}[/tex]

Now, finding k

[tex]{:\implies \quad \sf k=\dfrac{2\pi}{\lambda}=\dfrac{200\pi}{239}}[/tex]

[tex]{:\implies \quad \boxed{\bf{k\approx 2.63\:m^{-1}}}}[/tex]

Thus, expression for the electric field is:

[tex]{:\implies \quad \boxed{\bf{E=50\sin \bigg(4\pi \times 10^{7}t-\dfrac{263x}{100}\bigg)}}}[/tex]

(b) Now, here

[tex]{:\implies \quad \sf B_{0}=\dfrac{E_{0}}{c}=\dfrac{50}{3\times 10^{8}}}[/tex]

[tex]{:\implies \quad \boxed{\bf{B_{0}\approx 16.67×10^{-7}\:T}}}[/tex]

Thus, expression for the magnetic field:

[tex]{:\implies \quad \boxed{\bf{B_{y}=16.67\times 10^{-7}\sin \bigg(4\pi \times 10^{7}t-\dfrac{263x}{100}\bigg)\:T}}}[/tex]

(c) The electromagnetic wave propagates along Z-axis