Calculate the de Broglie wavelength of an electron that has been accelerated from rest through a potential difference of 1kV.

Calculate the de Broglie wavelength of an electron that has been accel

1.	Calculate the de Broglie wavelength of an electron that has been accelerated from rest through a potential difference of 1kV.
Answer» Solution :Energy acquired by the electron (as kinetic energy) after being aacelerated by a POTENTIAL DIFFERENCE of 1 kV. (i.e. 1000 volts) `= 1000 eV = 1000 XX 1.602 xx 10^(-19) J = 1.602 xx 10^(-16) J (1 eV = 1.602 xx 10^(-19)J)` i.e., Kinetic energy, `(1)/(2) mv^(2) = 1.602 xx 10^(-16) J or (1)/(2) xx 9.1 xx 10^(-31) v^(2)` or `v^(2) = 3.521 xx 10^(14) or v = 1.88 xx 10^(7) ms^(-1)` `:. lamda = (h)/(mv) = (6.626 xx 10^(-34) kg m^(2) s^(-1))/((9.1 xx 10^(-31) kg) xx (1.88 xx 10^(7) ms^(-1))) = 3.87 xx 10^(-11) m`