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The work functions of tungsten and sodiu...

The work functions of tungsten and sodium are `5.06 eV` and `2.53 eV` respectively. If the threshold wavelenth for sodium is `5896 Å`, then the threshold wavelength for the tungsten will be

A

`11792 Å`

B

`5896 Å`

C

`4312 Å`

D

`2948 Å`

Text Solution

Verified by Experts

The correct Answer is:
D
`(phi_(1))/(phi_(2)) = (lambda_(2))/(lambda_(1)) rArr (2.53)/(5.06) = (lambda)/(5896) rArr lambda = 2948 Å`
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ALLEN -SIMPLE HARMONIC MOTION-Exercise-01
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