Dual Nature Of Matter Question 5
Question 5 - 2024 (30 Jan Shift 1)
The work function of a substance is $3.0 eV$. The longest wavelength of light that can cause the emission of photoelectrons from this substance is approximately:
(1) $215 nm$
(2) $414 nm$
(3) $400 nm$
(4) $200 nm$
Show Answer
Answer: (2)
Solution:
For P.E.E. : $\lambda \leq \frac{h c}{W _e}$
$\lambda \leq \frac{1240 nm-eV}{3 eV}$
$\lambda \leq 413.33 nm$
$\lambda _{\max } \approx 414 nm$ for P.E.E.
