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

7112 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

A student heats a bar of chocolate in the microwave for one minute. When they remove the bar they observe that there are patches of melted chocolate with unmelted chocolate between them. Suggest the mechanism of how this happens.


Explain how Maxima and Minima occur in Young's double slit experiment


Explain the photo-electric effect and describe how the intensity of light effects rate of electron emission.


A 12V lamp, 36W is switched on for 1 hour. Find the energy supplied by the battery.


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:

© 2025 by IXL Learning