Assertion : Photosensitivity of a metal is hi | vedclass

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(A) The photosensitivity of a metal refers to its ability to emit photoelectrons when light of a suitable frequency is incident on it. A metal with a

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If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

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(A) The photosensitivity of a metal refers to its ability to emit photoelectrons when light of a suitable frequency is incident on it. A metal with a low work function $(\Phi_0)$ requires less energy to eject an electron, making it more photosensitive. Thus, the Assertion is correct.The work function is defined as $\Phi_0 = hf_0$, where $h$ is Planck's constant and $f_0$ is the threshold frequency. This is a standard physical relationship for the photoelectric effect. Thus, the Reason is also correct.Since the work function is defined by the threshold frequency $(f_0)$, and a smaller $f_0$ (and thus smaller $\Phi_0$) makes it easier to eject electrons, the Reason correctly explains why a small work function leads to high photosensitivity. Therefore, the correct option is $A$.

Assertion : Photosensitivity of a metal is high if its work function is small.
Reason : Work function $= hf_0$ where $f_0$ is the threshold frequency.

Similar Questions

When a photosensitive surface is irradiated by light of wavelengths $\lambda_1$ and $\lambda_2$,the kinetic energies of the emitted photoelectrons are $E_1$ and $E_2$ respectively. The work function of the photosensitive surface is:

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According to Einstein's photoelectric equation,the graph between the kinetic energy of emitted photoelectrons and the frequency of incident radiation is:

The work functions of Silver and Sodium are $4.6 \ eV$ and $2.3 \ eV$,respectively. The ratio of the slope of the stopping potential versus frequency plot for Silver to that of Sodium is :

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Assertion : Photosensitivity of a metal is high if its work function is small.Reason : Work function $= hf_0$ where $f_0$ is the threshold frequency.