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A stream of electrons from a heated fila...

A stream of electrons from a heated filament was passed between two charged plates kept at a potential difference V esu. If e and m are charge and mass of an electron, respectively, then the value of `h//lambda` (where `lambda` is wavelength associated with electron wave) is given by

A

`sqrt(2meV)`

B

meV

C

2meV

D

`sqrt(meV)`

Text Solution

Verified by Experts

The correct Answer is:
A
K.E of an electron `rarr` charge x potential
`rarr e xx v`
`therefore lambda=(h)/sqrt(2xxK>Exxm)`
`(h)/(lambda)=sqrt(2eVm)`
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