What is "half-life"?

Half-life is a term commonly used in radioactivity. It defines the time taken for a radioactive source to halve its activity. A radioactive source will emit radiation (energy) through the emission of particles or photons. How many of these particles are being released every second (or any arbitrary unit of time) determines a substance's activity. This can be seen mathematically through analysing the radioactive decay equations listed in the AQA formula list here: http://filestore.aqa.org.uk/subjects/AQA-PHYA4-5-INS-JUN12.PDF. Furthermore, the maths used to derive the equation for half-life, can be explained through these equations; I would be happy to show you if you wish. In conclusion, half life is how long it takes for a radioactive substance to become half as radioactive as it initially was. 

Answered by Evan T. Physics tutor

4235 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

Why does an absorption spectrum (of eg Helium) show dark lines?


Whats the effective resistance in a parallel and series circuit with a cell and two 12 ohms resistors ?


What is the difference between distance and displacement?


Describe simple harmonic motion (SHM). Sketch a displacement-time graph for a particle undergoing SHM and the corresponding velocity-time and acceleration-time graphs. Use these graphs to describe the relationship between accleration and displacment.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences