The work function of a substance is 4.0 eV. The longest wavelength of light that can cause photoelectric emission for it will be :

The work function of a substance is 4.0 eV. The longest wavelength of

1.	The work function of a substance is 4.0 eV. The longest wavelength of light that can cause photoelectric emission for it will be :
Answer» 400 mm 540 mm 220 mm 310 mm Solution :`omeg=hv_(0)=(HC)/(lambda_(0))` `:.lambda_(0)=(hc)/(OMEGA)=(6.02xx10^(-34)xx3xx10^(8))/(4xx1.6xx10^(-19))` `=310xx10^(-9)m` `rArr lambda_(0)=310 NM`

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The work function of a substance is 4.0 eV. The longest wavelength of light that can cause photoelectric emission for it will be :

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