Same chapter3 marksDifficulty: Medium
Light of frequency 1015 Hz falls on a metal of work function 2 eV. Find the maximum kinetic energy of the photoelectrons. Take h = 6.63 × 10−34 J s.
Dual Nature of Radiation and Matter
3 marksDifficulty: Medium
State the laws of the photoelectric effect and write Einstein's photoelectric equation.
Original Khojo Papers practice question — not from a past board paper.
Answer
Emission occurs only above a threshold frequency characteristic of the metal, whatever the intensity. Above it, the number of photoelectrons is proportional to the intensity and the maximum kinetic energy depends only on the frequency, not on the intensity. Emission is instantaneous. Einstein's equation is hν = φ0 + ½mv2max.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The wave theory of light can account for none of these, which is why the photon picture was needed.
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