(i) How does one explain the emission of electron from a photosensitive surfacewith te help ofEinstein's photoelectric equation ? (ii) The work function of the following metalsis given: Na = 2.75 eV, K = 2.3 eV, Mo = 4.17 eV and Ni = 5.15 eV. Whichof these metals will not cause photoelectricemission for radiation of wavelength 3300 Å from a laser source placed 1 m aways from these metals ? What happens if thelaser source is broughtnearer and placed50 cm away ?

(i) How does one explain the emission of electron from a photosensitiv

1.	(i) How does one explain the emission of electron from a photosensitive surfacewith te help ofEinstein's photoelectric equation ? (ii) The work function of the following metalsis given: Na = 2.75 eV, K = 2.3 eV, Mo = 4.17 eV and Ni = 5.15 eV. Whichof these metals will not cause photoelectricemission for radiation of wavelength 3300 Å from a laser source placed 1 m aways from these metals ? What happens if thelaser source is broughtnearer and placed50 cm away ?
Answer» Solution :IDENTIFICATION of metals/s which does/do not CAUSE photoelectric effect Photoelectric EMISSION. Effect produced `E=(hv)/(lamda)=(6.63xx10^(-34)xx3xx10^(8))/(3.3xx10^(-7)xx1.6xx10^(-19))eV` `=3.77eV` The work function of Mo and NI is more than the energy of the incident photons, so photo-electric emission WIL not take place from these metals. Kinetic energy of photo electrons will not change, only photoelectric current will change.

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