Question

Q. Find work function for a silver surface for which the threshold frequency of incident light is 1.1х1015 Hz.

Answer 1

Answer on Question #58591, Physics / Quantum Mechanics

Find work function for a silver surface for which the threshold frequency of incident light is $1.1 \times 10^{15} \, \text{Hz}$.

Find: A – ?

Given:

$u_{\min} = 1,1 \times 10^{15} \, \text{Hz}$

$h = 6,626 \times 10^{-34} \, \text{J} \times \text{s}$

Solution:

Equation of external photoelectric effect:

$$h u = A + \frac{m v_{\max}^2}{2} (1),$$

where $h u$ – energy of photon,

A – electron work function of the metal surface,

$\frac{m v_{\max}^2}{2}$ – the maximum kinetic energy of the electron

Of (1) $\Rightarrow h u_{\min} = A \, (2)$

Of (2) $\Rightarrow A = 7,29 \times 10^{-19} \, \text{J}$

$1 \, \text{eV} - 1,6 \times 10^{-19} \, \text{J}$

A $-7,29 \times 10^{-19} \, \text{J}$

$A = 4,56 \, \text{eV}$

Answer:

$4,56 \, \text{eV}$

https://www.AssignmentExpert.com