The work functions of Aluminium and Gold are $4.1 ~\mathrm{eV}$ and and $5.1 ~\mathrm{eV}$ respectively. The ratio of the slope of the stopping potential versus frequency plot for Gold to that of Aluminium is
Solution
<p>We are given the work functions of Aluminium and Gold as $4.1 ~\mathrm{eV}$ and $5.1 ~\mathrm{eV}$, respectively.</p>
<p>The stopping potential ($V_s$) is related to the frequency ($f$) of the incident light by the equation:</p>
<p>$eV_s = h(f - f_0)$</p>
<p>Where $e$ is the charge of an electron, $h$ is Planck's constant, and $f_0$ is the threshold frequency. The threshold frequency is related to the work function ($\phi$) by:</p>
<p>$\phi = hf_0$</p>
<p>So, we can write the equation for stopping potential as:</p>
<p>$V_s = \frac{h}{e}(f - \frac{\phi}{h})$</p>
<p>This equation represents a straight line with slope $\frac{h}{e}$. Therefore, the slope of the stopping potential versus frequency plot is the same for both Aluminium and Gold. The ratio of the slopes is:</p>
<p>$$\frac{\text{Slope for Gold}}{\text{Slope for Aluminium}} = \frac{\frac{h}{e}}{\frac{h}{e}} = 1$$</p>
<p>So , the ratio of the slope of the stopping potential versus frequency plot for Gold to that of Aluminium is 1.</p>
About this question
Subject: Physics · Chapter: Dual Nature of Matter and Radiation · Topic: Photoelectric Effect
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