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The stopping potential for the photo-ele...

The stopping potential for the photo-electrons emitted from a metal surface of work-function 1.7 eV is 10.4 eV. Find the wavelength of the radiation used. Also identify the energy-levels in hydrogen atom which will emit this wavelength.

A

The wavelength of light used is `1022 Å`

B

The wavelength of light used is `970.6 Å`

C

The light used is emitted by hydrogen gas sample which de-excites from `n = 3` to `n = 1`

D

The light used is emitted by hydrogen gas sample which de-excites from `n = 3` to `n = 1`

Text Solution

Verified by Experts

The correct Answer is:
A, C
`K_(max) = 10.4 eV , phi = 1.7 eV`
`E = 10.4 + 1.7 = 12.1 eV rArr n = 3 ` to `n = 1`
`12.1 = (1242.eVÅ)/(lambda)`
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Knowledge Check

  • Work function of photosensitive surface is 6.2 eV. If its stopping potential is 5V,then wavelength of incident radiation will be in……

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  • Photons of energy 1 eV and 2.5 eV successively illuminated a metal whose work function is 0.5 eV. The ratio of maximum speeds of emitted electron is

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    `2.186xx10^(-7)` m
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