Case: Read the passage and answer the question.
Einstein’s photoelectric equation is
\( K_{\max}=h\nu-\Phi \)
where \( \nu \) is the frequency of the incident radiation and \( K_{\max} \) is the maximum kinetic energy of a photoelectron. The work function \( \Phi \) is given as \( \Phi=h\nu_0 \). In terms of the stopping potential \( V_0 \), \( K_{\max}=eV_0 \).
In the photon picture of light, what is a packet of energy called?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → photon
NCERT (2026-27):
Particle Nature of Light: the Photon – “Photoelectric effect thus gave evidence to the strange fact that light in interaction with matter behaved as if it was made of quanta or packets of energy, each of energy h ν. … A definite value of energy as well as momentum is a strong sign that the light quantum can be associated with a particle. This particle was later named photon.”