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The variation of the stopping potential V0 with the frequency v of the light incident on two different photosensitive M1 and M2

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\documentclass{article}
\usepackage{amsmath}
\usepackage{graphicx}
\begin{document}

\section*{Photoelectric Effect: Variation of Stopping Potential with Frequency}

According to Einstein's photoelectric equation:

\[
eV_0 = h\nu - \phi
\]

Where:
\begin{itemize}
    \item \( V_0 \): Stopping potential
    \item \( \nu \): Frequency of incident light
    \item \( h \): Planck's constant
    \item \( \phi \): Work function of the material
    \item \( e \): Charge of the electron
\end{itemize}

Rewriting the equation:

\[
V_0 = \frac{h}{e}\nu - \frac{\phi}{e}
\]

This is a linear equation of the form \( V_0 = m\nu + c \), where:
\begin{itemize}
    \item Slope \( m = \frac{h}{e} \)
    \item Y-intercept \( = -\frac{\phi}{e} \)
    \item Threshold frequency \( \nu_0 = \frac{\phi}{h} \) (when \( V_0 = 0 \))
\end{itemize}

\section*{Comparison Between Two Materials: \( M_1 \) and \( M_2 \)}

\begin{itemize}
    \item Both materials will have straight-line graphs of \( V_0 \) vs. \( \nu \), with the \textbf{same slope} \( \left( \frac{h}{e} \right) \) since \( h \) and \( e \) are constants.
    \item The \textbf{intercepts on the frequency axis} (i.e., threshold frequencies) will differ depending on their work functions.
    \item If \( \phi_1 < \phi_2 \), then \( \nu_{0,1} < \nu_{0,2} \). So, material \( M_1 \) will start emitting photoelectrons at a lower frequency.
\end{itemize}

\textbf{Conclusion:}
\begin{itemize}
    \item The graph of \( V_0 \) vs. \( \nu \) is a straight line for both materials.
    \item The material with a lower work function requires a lower threshold frequency.
    \item Both lines are parallel but have different intercepts on the frequency axis.
\end{itemize}

\end{document}
 

Posted by

Saumya Singh

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