English National Curriculum - Science
Mission Objectives
Define the count rate of a radioactive source.
Explain what is meant by the half-life of a radioactive source.
Calculate count rates after a given number of half-lives (Higher tier only).
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Words and meanings to learn
Half-life
The time it takes for half of a radioactive substance to decay.
Radioactive decay
The process by which an unstable atomic nucleus loses energy by emitting radiation in the form of alpha, beta particles, or gamma rays, leading to the transformation into a more stable nucleus
Becquerel (Bq)
is a unit used to measure radioactivity. It represents the number of nuclear decays per second.
activity
The rate at which a sample of radioactive material undergoes decay, measured in becquerels (Bq), where 1 Bq equals one decay per second.
Count rate
the number of radioactive decays detected per second by a radiation detector, such as a Geiger counter.
Samantha is an accomplished science educator whose current work centres on curriculum design and professional development, supporting teachers to deliver high-quality science education through evidence-informed approaches. She is a former Head of Chemistry and Sixth Form Tutor with extensive Key Stage 4 and 5 experience, and has worked as an AQA examiner, giving her valuable insight into assessment standards and what students need to succeed.
Underpinning this is a strong foundation in applied science built across a range of industry roles. Samantha has held scientific roles at John Smith's Brewery, Yorkshire Water and WasteCare, where she led technical projects, drove operational efficiencies and ensured compliance with industry standards. Across these roles she has first-hand experience of how scientific knowledge translates into measurable outcomes in professional and commercial environments.
In her spare time, Samantha enjoys playing the accordion with her local orchestra and has recently taken up cricket.
Simulation: Phet simulation
Dice, smarties, counters, measuring cylinders
Expert film
Mission assignment film
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