Light wave is travelling along +y-direction. If the corresponding $\vec{E}$ vector at any time is along the +z-axis. Then the direction of $\vec{B}$ vector at this time is along:

Electromagnetic Waves

NEET

y-axis

+x-axis

-x-axis

-z-axis

Solution:

In an electromagnetic wave, the direction of propagation is given by the direction of the Poynting vector, which is parallel to $\vec{E} \times \vec{B}$ . The wave is travelling along the +y-direction, so the direction of propagation is $\hat{y}$ . The electric field $\vec{E}$ is along the +z-axis, so its direction is $\hat{z}$ . Let the direction of the magnetic field $\vec{B}$ be $\hat{b}$ . Then, $\hat{z} \times \hat{b}$ must be in the direction of $\hat{y}$ . Using the right-hand rule or vector cross product properties, we know that $\hat{z} \times \hat{x} = \hat{y}$ . Therefore, the direction of $\vec{B}$ must be along the +x-axis.

Light wave is travelling along +y-direction. If the corresponding E⃗\vec{E}E vector at any time is along the +z-axis. Then the direction of B⃗\vec{B}B vector at this time is along:

Solution:

Related Questions

Light wave is travelling along +y-direction. If the corresponding $\vec{E}$ vector at any time is along the +z-axis. Then the direction of $\vec{B}$ vector at this time is along: