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In a photoemissive cell, with exiciting ...

In a photoemissive cell, with exiciting wavelength is changed to `(33lambda)/(4)`, the speed of the fastest emitted electron will be

A

`vsqrt(3/4)`

B

`vsqrt(4/3)`

C

less than `vsqrt(3/4)`

D

greater then `vsqrt(4/3)`

Text Solution

Verified by Experts

(D) `1/2 mv^(2) =(hc)/(lambda)-phi`
`1/2 mv'^(2)=(hc)/((3lambda//4))-phi=(4hc)/(3lambda)-phi`
Clearly `v' gt sqrt(4/3) v`
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