Why does an α particle cause more ionisation than a β particle if they have the same kinetic energy?

An alpha particle has a much larger volume than a β particle, so when passing by an atom it is more likely to collide with an electron and knock it out of the atom causing the atom to be ionised (meaning it is now an ion) and so more ions are created, making it more ionising than a β particle. Another reason why α particles cause more ionisation is because it has more charge. An α particle has a charge of +2, which is the opposite charge to the electrons orbiting the atoms, so the α particle attracts the electrons and pulls them away from the atom, leaving it with fewer electrons, making it an ion. On the other hand, β particles are electrons, so they have the same charge as the electrons orbiting the atom, so they will only push electrons back towards the atom, meaning it is unlikely that β particles iononise through this method.

Answered by Physics tutor

8540 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

A wire has length l, cross-sectional area a, resistivity p and resistance R. It is compressed to a third of its original length but its volume and resistivity are constant. Show its new resistance is R/9.


How, given the threshold frequency and the kinectic enery of a photon, do you determine the frequency of the phton?


Use band theory to explain the changes in the resistance of an intrinsic semiconductor as temper changes.


An electrical heater supplies 500J of heat energy to a copper cylinder of mass 32.4g Find the increase in temperature of the cylinder. (Specific heat capacity of copper = 385 J*kg^-1*Celsius^-1


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning