If you’d like to practise the material covered in this video, check out our platform at www.cognitoedu.org - it's totally free, and has been built to make learning and revision as easy as possible. The main features are: - Lessons organised by topic, only the lessons relevant to your specific exam board and tier are shown. - Automatic progress tracking. Progress bars tell you what you’re doing well at, and what you need to spend some time on. - Practise quizzes so you can test your knowledge. You can quiz yourself on any combination of topics you like. - A huge number of fully-hinted questions that take you step-by-step through some of the trickiest calculations & concepts. - A comprehensive bank of past exam papers, organised both by year, and also by topic. Amadeus & Tom
Cognito - i have a question about your website if you have your time free - how can you change your course - for example from combined science to separate science?
how is short half life good tho?eg if it has a half life of 1 day ,then it was emit radiation for one day and after that ,it will emit for another one day ?Or do you remove the radiation after it has been one day ? pls reply
A short half-life is good for medical tracers because it means that the amount of radiation being emitted into your body reduces rapidly, reducing the risk of damage to your cells. If a radioactive isotope has a half-life of 1 day it means that the amount of radiation being emitted by the isotope halves every day. For example if a source of radiation was emitting 1000 particles per second and it had a half-life of 1 day, it would mean that it would be emitting 500 particles per second once 24 hours had passed. If another day passed, it would be emitting around 250 particles per second and it would continue halving for every day that passed.
