Discuss the Einstien's explanation for the photoelectric effect.

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$\rightarrow$ In $1905,$ Einstien gave a historical explanation of the photoelectric effect.
For which he was awarded the Nobel prize in physics in $1921$.
$\rightarrow$ Einstein accepted Max Planck's concept of radiation.
$\rightarrow$ According to this concept, the energy of radiation is not continuous.
Radiation is composed of discrete units of energy, $($Bundles of energy$)$
These units of energy are called quanta or photons.
Each quantum (photon) has energy $E =h v$.
Where, $h=$ Planck's constant
$h=6.625 \times 10^{-34} J s$
$v=$ Frequency of radiation
$\rightarrow$ When radiation is incident on a metal surface, the electrons in the metal interact with the quanta of the radiation.
If the energy of quantum $(h v)$ is greater than the work function $\left(\phi_0\right)$ of a given metal, the electron absorbs this quantum. i.e. the full energy of the quantum $(h v)$ is absorbed and is emitted from the metal with a maximum kinetic energy $K _{\max }$.
Thus, $K _{ max }=h v-\phi_0$
$\rightarrow$ This equation is called Einstein's equation of photoelectric effect.

$\rightarrow$ If a photon interacts with an strongly bound electron than electron requires more energy to be ejected.
So it is emitted with less energy than $K _{\max }$.

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$\vec{\text{E}}=\text{B}_0\text{c}\sin(\text{kx}+\omega\text{t}) \hat{\text{k}}\frac{\text{V}}{\text{m}}$

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$\frac{2\epsilon_0}{\text{c}}\hat{\text{j}}\cos\text{kz}\cos\omega\text{t}$
$\frac{2\epsilon_0}{\text{c}}\hat{\text{j}}\sin\text{kz}\cos\omega\text{t}$
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$0.095\mu\text{T}$
$0.124\mu\text{T}$
$0.089\mu\text{T}$
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$\text{B}_\text{z}=1.1\times10^{-7}\cos\pi\times10^{11}\Big(\text{t}-\frac{\text{x}}{\text{c}}\Big)$
$\text{E}_\text{y}=11\cos2\pi\times10^{11}\Big(\text{t}-\frac{\text{x}}{\text{c}}\Big),$
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A plane electromagnetic wave travels in free space along $x-$ axis. At a particular point in space, the electric field along $y-$ axis is $9.3Vm^{-1.}$ The magnetic induction $(B)$ along $z-$ axis is: