English National Curriculum - Science
Mission Objectives
Describe the differences between direct current (DC) and alternating current (AC)
Identify and explain the function of the main parts of a UK three-pin plug and electrical cable
Explain how earthing, double insulation and fuses protect users from electric shocks and damage to electrical appliances
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Words and meanings to learn
direct current (DC)
an electric current that flows in one direction only, supplied by batteries and cells
frequency
the number of complete cycles of alternating current per second, measured in hertz (Hz)
earth wire
a safety wire in a plug that connects the metal casing of an appliance to the ground to prevent electric shocks
double insulation
a safety feature where appliances have two layers of insulating material so no live parts can be touched, removing the need for an earth wire
alternating current (AC)
an electric current that repeatedly changes direction; the UK mains supply is AC at 230 V and 50 Hz
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.
National grid demo set up.
Oscilloscope connected to a power pack with AC/DC channels.
Plug wiring class practical: 3-pin plugs, screw drivers, cable, wire cutters, wire strippers.
Expert film
Mission assignment film
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