Define the terms (a) threshold frequency, and (b) stopping potential. How were these tenns incorporated in Einstein's photoelectric equation?

Define the terms (a) threshold frequency, and (b) stopping potential.

1.	Define the terms (a) threshold frequency, and (b) stopping potential. How were these tenns incorporated in Einstein's photoelectric equation?
Answer» Solution :(a) Threshold frequency `(v_(0))` is minimum frequency for a metal SURFACE below which no photoelectric emission is possible, no matter how intense the incident radiation may be or how long it falls on the surface. (b) Stopping potential is that minimum negative (retarding) potential `(V_(0))` given to the plate of a photoelectric tube for which the PHOTOCURRENT STOPS or becomes zero. Stopping potential is a measure of MAXIMUM kinetic energy of photoelectrons being PRODUCED for a given incident radiation. As per Einstein.s photoelectric equation, we have `K_("max")=hv-phi_(0)` but work function `phi_(0)=hv_(0)` and `K_("max")=eV_(0)` so the equation becomes `eV_(0)=hv-hv_(0)` `rArrH(v-v_(0))=eV_(0)` In this way, `v_(0)` and `V_(0)` are incorporated in Einstein.s photoelectric equation.

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Define the terms (a) threshold frequency, and (b) stopping potential. How were these tenns incorporated in Einstein's photoelectric equation?

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