A monochromatic light source of intensity 5 m W emits (8x10^15) photons per second . This light ejects photoelectrons from a metal surface. The stopping potential for this setup is 2.0 V. Calculate the work function of the metal.

A monochromatic light source of intensity 5 m W emits (8x10^15) photon

1.	A monochromatic light source of intensity 5 m W emits (8x10^15) photons per second . This light ejects photoelectrons from a metal surface. The stopping potential for this setup is 2.0 V. Calculate the work function of the metal.
Answer» Solution :`P= 5 X 10^(-3)W` `E=p/n=6.25 xx 10^(-19)J` `E=3.8eV` `W_(0)=E-eV_(0)` `=(3.9-2)eV_(0)` `W_(0)=1.8eV`

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A monochromatic light source of intensity 5 m W emits (8x10^15) photons per second . This light ejects photoelectrons from a metal surface. The stopping potential for this setup is 2.0 V. Calculate the work function of the metal.

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