Question 376: Dual Nature of Matter and Radiation

Question

A metal surface is illuminated by light of given intensity and frequency to cause photoemission. If the intensity of illumination is reduced to one fourth of its original value then the maximum KE of the emitted photoelectrons would be

Accepted Answer

The maximum kinetic energy of photoelectrons is given by $\mathrm{KE}_{	ext {max }}=h\left(
u-
u_0ight)\quad	ext{.... (i)}$
where, $h=$ Planck's constant,
$
u=$ frequency of radiation
and $
u_0=$ threshold frequency.
It can be seen from Eq. (i), that the maximum KE of emitted photoelectron is proportional to the frequency of radiation and is independent of the intensity of radiation, so it remains unchanged.'

Answer

twice the original value

Answer

four times the original value

Answer

one fourth of the original value

Answer

unchanged

Dual Nature of Matter and Radiation

A metal surface is illuminated by light of given intensity and frequency to cause photoemission. If the intensity of illumination is reduced to one fourth of its original value then the maximum KE of the emitted photoelectrons would be

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