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 with over 15 years of leadership experience and a strong background in scientific analysis. She has a proven record of leading departments effectively, improving practice, and working collaboratively with stakeholders.
In her current work, Samantha embeds evidence-informed pedagogical principles such as retrieval practice, clear modelling, and effective sequencing to support high-quality curriculum design and professional development. She draws on assessment insight and common misconceptions to help teachers secure strong student understanding.
She is a former Head of Chemistry and Sixth Form Tutor at Ilkley Grammar School, with extensive Key Stage 4 and 5 experience, and an AQA examiner, giving her valuable insight into assessment standards and exam requirements.
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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