If m is the mass of an electron and c the speed of light, the ratio of the wavelength of a photon of energy E to that of the electron of the same ener

Monjur Alahi

If m is the mass of an electron and c the speed of light, the ratio of the wavelength of a photon of energy E to that of the electron of the same energy is
A. `csqrt((2m)/(E))`
B. `sqrt((2m)/(E))`
C. `sqrt((2m)/(cE))`
D. `sqrt((m)/(E))`


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Salim Ahmed Kawsar

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Correct Answer - A
(a) : energy of photon, `E=hv=(hc)/(lamda_(ph))`
where `lamda_(ph)` is the wavelength of a photon, `lamda_(ph)=(hc)/(E)`
Wavelength of the electron, `lamda_(e)=(h)/(sqrt(2mE))`
`:.(lamda_(ph))/(lamda_(e))=(hc)/(E)xx(sqrt(2mE))/(h)=csqrt((2m)/(E))`

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