Given:
The kinetic energy of the electron, Ke =10 keV, the kinetic energy of the proton, K p =100 keV, the mass of the electron, m e =9.11× 10 −31 kg and the mass of the proton, m p =1.67× 10 −27 kg.
The kinetic energy of the electron can be given as, Ke=12mev2e,ve=√2Keme ...(1)
The kinetic energy of the proton can be given as, Kp=12mpv2p,vp=√2Kpmp ...(2)
By dividing equation (1) by equation (2), we get
vevp=√2Kemp√2Kpme
By substituting the given values in the above equation, we get
vevp=√2(10)×1.67×10−27√2(100)×9.11×10−31
ve=13.5vp
The above relation shows that the electron is moving faster than the proton.