Question

In an electron microscope the electrons are accelerated by a voltage of 25 KV If the
voltage is changed to 225 kV then the de-Brogie wavelength associated with the
electrons would​

Answer 1

then the de-Brogie wavelength associated with the

electrons would​ be decreased by  3 times the original wavelength.

Explanation:

we know that

Λ ∝ 1 / √ v  . ( Λ = h / p ) and ( p = √ 2mE) , ( E = eV)

( Λ1 / Λ2 ) = (√ V2 / √ V1 )

Λ1 / Λ2 = 3

So Λ2 = Λ1 / 3