The work functions (in eV) of Mg, Cu, Ag, Na | vedclass

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(C) The energy of the incident photon is given by $E = \frac{hc}{\lambda}$.Substituting the values: $E = \frac{6.6 	imes 10^{-34} \ J \cdot s 	imes

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(C) The energy of the incident photon is given by $E = \frac{hc}{\lambda}$.Substituting the values: $E = \frac{6.6 	imes 10^{-34} \ J \cdot s 	imes 3 	imes 10^8 \ m/s}{300 	imes 10^{-9} \ m} = 6.6 	imes 10^{-19} \ J$.Converting this energy into $eV$: $E = \frac{6.6 	imes 10^{-19} \ J}{1.6 	imes 10^{-19} \ J/eV} = 4.125 \ eV$.Electrons are ejected if the energy of the incident photon is greater than or equal to the work function $(\Phi)$ of the metal.Comparing $4.125 \ eV$ with the given work functions:$Mg (3.7 \ eV) $Cu (4.8 \ eV) > 4.125 \ eV$ (Not ejected)$Ag (4.3 \ eV) > 4.125 \ eV$ (Not ejected)$Na (2.3 \ eV) Thus,electrons will be ejected from $2$ metals ($Mg$ and $Na$).

The work functions (in $eV$) of $Mg, Cu, Ag, Na$ respectively are $3.7, 4.8, 4.3, 2.3$. From how many metals,the electrons will be ejected if their surfaces are irradiated with an electromagnetic radiation of wavelength $300 \ nm$ ?
$(h=6.6 \times 10^{-34} \ Js, 1 \ eV=1.6 \times 10^{-19} \ J)$

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The work functions (in $eV$) of $Mg, Cu, Ag, Na$ respectively are $3.7, 4.8, 4.3, 2.3$. From how many metals,the electrons will be ejected if their surfaces are irradiated with an electromagnetic radiation of wavelength $300 \ nm$ ?$(h=6.6 \times 10^{-34} \ Js, 1 \ eV=1.6 \times 10^{-19} \ J)$