Assuming photoemission to take place,the fact | vedclass

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(D) According to Einstein's photoelectric equation: $\frac{hc}{\lambda} = W_0 + \frac{1}{2}mv_{\max}^2$.Assuming the work function $W_0$ is negligible

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$\frac{1}{2}$

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(D) According to Einstein's photoelectric equation: $\frac{hc}{\lambda} = W_0 + \frac{1}{2}mv_{\max}^2$.Assuming the work function $W_0$ is negligible compared to the incident photon energy $\frac{hc}{\lambda}$,we have $\frac{1}{2}mv_{\max}^2 \approx \frac{hc}{\lambda}$.This implies $v_{\max}^2 \propto \frac{1}{\lambda}$,or $v_{\max} \propto \frac{1}{\sqrt{\lambda}}$.Let the initial wavelength be $\lambda_1 = \lambda$ and the final wavelength be $\lambda_2 = 4\lambda$.The ratio of the maximum velocities is $\frac{v_{\max, 2}}{v_{\max, 1}} = \sqrt{\frac{\lambda_1}{\lambda_2}} = \sqrt{\frac{\lambda}{4\lambda}} = \sqrt{\frac{1}{4}} = \frac{1}{2}$.Thus,the maximum velocity becomes half of its initial value.

Assuming photoemission to take place,the factor by which the maximum velocity of the emitted photoelectrons changes when the wavelength of the incident radiation is increased four times,is

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