The kinetic energy of an electron is 5 xx 10^(5) eV (electron volts). Calculate the wavelength of the wave associated with the electron. The mass of the electron may be taken as 10^(-30) kg

The kinetic energy of an electron is 5 xx 10^(5) eV (electron volts).

1.	The kinetic energy of an electron is 5 xx 10^(5) eV (electron volts). Calculate the wavelength of the wave associated with the electron. The mass of the electron may be taken as 10^(-30) kg
Answer» Solution :`1 EV = 1.6 xx 10^(-19)J, KE = (1)/(2) mv^(2) or (5 xx 10^(-5)) (1.6 xx 10^(-19)) = (1)/(2) xx 10^(-30) xx v^(2)` or `v^(2) = 16 xx 10^(6) or v = 4 xx 10^(3) m s^(-1)` Hence, `lamda = (h)/(mv) = (6.626 xx 10^(-34) kg m^(2) s^(-1))/(10^(-30) kg xx 4 xx 10^(3) ms^(-1)) = 1.66 xx 10^(-7) m`