Even though an electric field $E$ exerts a force $qE$ on a charged particle yet the electric field of an $EM$ wave does not contribute to the radiation pressure (but transfers energy). Explain.
Even though an electric field $E$ exerts a force $qE$ on a charged particle yet the electric field of an $EM$ wave does not contribute to the radiation pressure (but transfers energy). Explain.
Electric field of electromagnetic waves is an oscillating field and so the electric force caused by it on charged particle. This electric force averaged over an integral number of cycles is zero since its direction changes every half cycle. Hence electric field is not responsible for radiation pressure.
Similar Questions
For the plane electromagnetic wave given by $\mathrm{E}=\mathrm{E}_0 \sin (\omega \mathrm{t}-\mathrm{kx})$ and $\mathrm{B}=\mathrm{B}_0 \sin (\omega \mathrm{t}-\mathrm{kx})$, the ratio of average electric energy density to average magnetic energy density is
For the plane electromagnetic wave given by $\mathrm{E}=\mathrm{E}_0 \sin (\omega \mathrm{t}-\mathrm{kx})$ and $\mathrm{B}=\mathrm{B}_0 \sin (\omega \mathrm{t}-\mathrm{kx})$, the ratio of average electric energy density to average magnetic energy density is
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A monochromatic beam of light has a frequency $v = \frac{3}{{2\pi }} \times {10^{12}}\,Hz$ and is propagating along the direction $\frac{{\hat i + \hat j}}{{\sqrt 2 }}$. It is polarized along the $\hat k$ direction. The acceptable form for the magnetic field is
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A plane electromagnetic wave of frequency $25 \;MHz$ travels in free space along the $x$ -direction. At a particular point in space and time, $E = 6.3\,\hat j\;\,V/m$. What is $B$ at this point?
A plane electromagnetic wave of frequency $25 \;MHz$ travels in free space along the $x$ -direction. At a particular point in space and time, $E = 6.3\,\hat j\;\,V/m$. What is $B$ at this point?
The electric field of a plane polarized electromagnetic wave in free space at time $t = 0$ is given by an expression
$\vec E(x,y) = 10\hat j\, cos[(6x + 8z)]$
The magnetic field $\vec B (x,z, t)$ is given by : ($c$ is the velocity of light)
The electric field of a plane polarized electromagnetic wave in free space at time $t = 0$ is given by an expression
$\vec E(x,y) = 10\hat j\, cos[(6x + 8z)]$
The magnetic field $\vec B (x,z, t)$ is given by : ($c$ is the velocity of light)
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Suppose that the electric field amplitude of an electromagnetic wave is $E_{0}=120\; N / C$ and that its frequency is $v=50.0\; MHz$.
$(a)$ Determine, $B_{0}, \omega, k,$ and $\lambda .$
$(b)$ Find expressions for $E$ and $B$
Suppose that the electric field amplitude of an electromagnetic wave is $E_{0}=120\; N / C$ and that its frequency is $v=50.0\; MHz$.
$(a)$ Determine, $B_{0}, \omega, k,$ and $\lambda .$
$(b)$ Find expressions for $E$ and $B$