<p>When a photosensitive metal surface is exposed to monochromatic light of frequency f, the emitted photoelectrons possess a maximum speed <span class="equation">\(v_{max}\)</span>​. A straight-line graph is obtained between <span class="equation">\(v^2_{max}\)</span>​​​​​​​(on the y-axis) and frequency f(on the x-axis), as shown in the figure.</p>

<p><img alt="" src="https://school.achievam.com/upload/questionbank/question/que_1759642420.jpg" style="height:120px; width:157px" />​​​​​​​</p>

<p>Using the graph, derive expressions for:<br />
<strong>(i)</strong> Planck&rsquo;s constant h, and<br />
<strong>(ii)</strong> The work function <span class="equation">\(\phi\)</span>&nbsp;of the metal, in terms of the slope &alpha;, intercept &beta;, and mass m of the electron.</p>