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When a metal surface is illuminated by l...

When a metal surface is illuminated by light wavelengths `400 nm` and `250 nm` , the maximum velocities of the photoelectrons ejected are `upsilon` and `2 v` respectively . The work function of the metal is
`( h = "Planck's constant" , c = "velocity of light in air" )`

A

`2hc xx 10^(6) J`

B

`1.5hc xx 10^(6) J`

C

`hc xx 10^(6) J`

D

`0.5hc xx 10^(6) J`

Text Solution

Verified by Experts

The correct Answer is:
A
`(hc)/lambda=w+1/2mv^(2)`
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NARAYNA-DUAL NATURE-LEVEL-III
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