# Calculate the de- Broglie wavelength of electron accelerated through 100 volt

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Calculate the de- Broglie wavelength of electron accelerated through 100 volt

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We have the kinetic energy of an electron accelerated through a potential difference of V volts is given by the equation:

Ek = 1/2mv2 = eV where e is the electron charge (1.6x10-19 C)

The mass of an electron = 9.11 x 10-31 kg

and so v = √(2eV/m) = √(2x1.6x10-19x100/9.11 x 10-31) = 5.92x106 m/s

Therefore: wavelength = h/mv = h/[9.11x10- 31x5.92x106]

= 6.63x10-34/[9.11x10- 31x5.92x106]

= 0.12 x 10-9 m