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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

`2 hc xx 10^(6) J`

B

`1.5 hc xx 10^(6) J`

C

`hc xx 10^(6) J`

D

`0.5 hc xx 10^(6) J `

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The correct Answer is:
A
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