Light of wavelength $λ$ falls on a metal having work function $\frac{hc}{λ_0}$. Photoelectric effect will take place only if:
Answer & explanation
Correct answer: option 3
According to Einstein’s photoelectric equation
$K=\frac{hc}{λ}-\frac{hc}{λ_0}$
K is positive, i.e., photoelectric emission will take place if
$\frac{hc}{λ}-\frac{hc}{λ_0}$ or $λ≤λ_0$