What is de Broglie wavelength of an electron after being accelerated through a potential difference of 25 kV in a television set?

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We must first consider that the DeBroglie wavelength is calculated by (lamda)=h/p where h=Planck's Constant and p=momentum of the particle. To then calculate the momentum of the electron using p=mv, where m=mass of electron and v=electron velocity. We are not given the electron velocity but we do know that it is accelerated by 25kV. We can therefore set up the problem eV=1/2mv2, where e=elementary charge, V=potential difference,m=electron mass and v=electron speed. Re-arranging, we will get v=squareroot(2eV/m) which we can enter back into the original equation to get:
(lamda)=h / m*(sqrt(2eV/m)) which we have all of the values for. The final result will give a DeBroglie wavelength of 7.8x10-12m or 7.8pm.