2007-07-07 05:41:36 · 4 answers · asked by kb1990 1 in Science & Mathematics ➔ Physics
When a metallic surface is exposed to electromagnetic radiation above a threshold frequency (which is specific to the surface of the material), the photons are absorbed and current is produced. No electrons are emitted for radiation with a frequency below that of the threshold because the electrons are unable to gain sufficient energy to overcome the electrostatic barrier presented by the termination of the crystalline surface (the material's work function).
Therefore, photoelectric effect isn't true with spectacles because the necessary condition of frequency above the threshold frequency is not satisfied. It involves more than just the emission of electrons.
2007-07-07 05:52:56 · answer #1 · answered by Shobiz 3 · 0⤊ 0⤋
The photoelectric effect occurs in vacuum given materials with a low work function (re Fermi level as continuum or highest occupied molecular orbital in discrete systems). Eyeglass lenses are not in vacuum, they are dielectrics, and they do not have low work functions unless they are ground from surface hydrogen-terminated diamond (negative work function into vacuum).
2007-07-07 12:48:13 · answer #2 · answered by Uncle Al 5 · 0⤊ 1⤋
Yes it is possible but the work function of the materials in the glass is extremely high.
2007-07-07 12:56:58 · answer #3 · answered by ag_iitkgp 7 · 0⤊ 0⤋
no. metals and semiconductors only.
2007-07-07 12:46:17 · answer #4 · answered by Anonymous · 0⤊ 1⤋