Question 297: Dual Nature of Matter and Radiation

Question

Two photons having energies twice and thrice the work function of metal are incident one after another on the metal surface. Then the ratio of maximum velocities of the photoelectrons emitted in the two cases is respectively

Accepted Answer

$$
\begin{aligned}
& K \cdot E_{\max }=h 
u-\phi_0 \
& 	ext { Given: } E_1=2 \phi_0 	ext { and } E_2=3 \phi_0 \
& \Rightarrow K \cdot E_1=2 \phi_0-\phi_0=\phi_0 \
& \Rightarrow K \cdot E_2=3 \phi_0-\phi_0=2 \phi_0 \
& 	ext { but, } K \cdot E_1=\frac{1}{2} m v_1^2 	ext { and } \mathrm{K} \cdot \mathrm{E}_2=\frac{1}{2} \mathrm{mv}_2^2 \
	herefore \quad & \frac{\mathrm{~K} \cdot \mathrm{E}_1}{\mathrm{~K} \cdot \mathrm{E}_2}=\frac{\mathrm{V}_1^2}{\mathrm{~V}_2^2}=\frac{1}{2} \
	herefore \quad & \frac{\mathrm{~V}_1}{\mathrm{~V}_2}=\frac{1}{\sqrt{2}}
\end{aligned}
$$

Answer

$\sqrt{3}: 3$

Answer

$\sqrt{2}: \sqrt{3}$

Answer

$1: \sqrt{2}$

Answer

$\sqrt{3}: 1$

Dual Nature of Matter and Radiation

Two photons having energies twice and thrice the work function of metal are incident one after another on the metal surface. Then the ratio of maximum velocities of the photoelectrons emitted in the two cases is respectively

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