MCQ
The direction of poynting vector represents
  • A
    The direction of electric field
  • B
    The direction of magnetic field
  • The direction of propagation of $EM$ wave
  • D
    The direction opposite to the propagation of $EM$ wave

Answer

Correct option: C.
The direction of propagation of $EM$ wave
c
(c)

$\bar{S}=\frac{\vec{E} \times \bar{B}}{\mu_0}$

$\vec{E} \times \vec{B} \Rightarrow$ direction of wave propagation

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

The frequency and the intensity of a beam of light falling on the surface of photoelectric material are increased by a factor of two. This will :
The decay constants of a radioactive substance for $\alpha $ and $\beta $ emission are ${\lambda _\alpha }$ and ${\lambda _\beta }$ respectively. If the substance emits $\alpha $ and $\beta $ simultaneously, then the average half life of the material will be
This question has Statement $-1$ and Statement $-2$ . Of the four choices given after the statements, choose the one that best describes the two statements

Statement $-1$ : Sky wave signals are used for long distance radio communication. These signals are in general, less stable than ground wave signals

Statement $-2$ : The state of ionosphere varies from hour to hour, day to day and season to season

A particle of charge per unit mass $\alpha$ is released from origin with a velocity $\bar{v}=v_0 \vec{i}$ in a uniform magnetic field $\bar{B}=-B_0 \hat{k}$. If the particle passes through $(0, y, 0)$ then $y$ is equal to
An infinite plane sheet of charge having uniform surface charge density $+\sigma_5 \mathrm{C} / \mathrm{m}^2$ is placed on $\mathrm{x}-\mathrm{y}$ plane. Another infinitely long line charge having uniform linear charge density $+\lambda_e \mathrm{C} / \mathrm{m}$ is placed at $z=4 \mathrm{~m}$ plane and parallel to $y$-axis. If the magnitude values $\left|\sigma_s\right|=2\left|\lambda_{\mathrm{e}}\right|$ then at point $(0,0,2)$, the ratio of magnitudes of electric field values due to sheet charge to that of line charge is $\pi \sqrt{\mathrm{n}}: 1$. The value of $n$ is
Correct pair is ..........
The $P-V$ diagram of a diatomic ideal gas system going under cyclic process as shown in figure. The work done during an adiabatic process $CD$ is (use $\gamma=1.4$) (in $J$)
The escape velocity from the surface of earth is ${V_e}$. The escape velocity from the surface of a planet whose mass and radius are $3$ times those of the earth will be
The device that does not work on the principle of mutual induction is
Find the value of $I$ ?................ $\mathrm{A}$