Question 319: Dual Nature of Matter and Radiation

Question

Maximum kinetic energy of photon is '$E$' when wavelength of incident radiation is '$\lambda$'. If wavelength of incident radiations is reduced to $\frac{\lambda}{3}$ then energy of photon becomes four times. Then work function of the metal is

Accepted Answer

$\mathrm{E}=\frac{\mathrm{hc}}{\lambda}-\phi_0
$ ....... (i)
Given: $\lambda=\frac{\lambda}{3}$ and $\mathrm{E}=4 \mathrm{E}$
$\begin{aligned}
& 4 \mathrm{E}=\frac{\mathrm{hc}}{\lambda / 3}-\phi_0 \quad 	ext{..... (ii)} \
& =\frac{3 \mathrm{hc}}{\lambda}-\phi_0 \
& 4\left(\frac{\mathrm{hc}}{\lambda}-\phi_0ight)=\frac{3 \mathrm{hc}}{\lambda}-\phi_0 \quad 	ext{.....(From (i))}\
& \frac{4 \mathrm{hc}}{\lambda}-4 \phi_0=\frac{3 \mathrm{hc}}{\lambda}-\phi_0 \
& \frac{\mathrm{hc}}{\lambda}=3 \phi_0 \
& \phi_0=\frac{\mathrm{hc}}{3 \lambda} \
\end{aligned}$

Answer

$\frac{3 h c}{\lambda}$

Answer

$\frac{\mathrm{hc}}{3 \lambda}$

Answer

$\frac{h c}{\lambda}$

Answer

$\frac{\mathrm{hc}}{2 \lambda}$

Dual Nature of Matter and Radiation

Maximum kinetic energy of photon is 'E' when wavelength of incident radiation is '\lambda'. If wavelength of incident radiations is reduced to \frac{\lambda}{3} then energy of photon becomes four times. Then work function of the metal is

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