1. Fred finds a hair dryer at home. A part of the cable is broken and he sees a golden-brown wire inside the blue outer jacket. What are the blue jacket and golden-brown wire made of? Are the materials metals or non-metals? 2 What is the difference between the electrical conductivity of metals and non-metals?
I just realised that a cable is made of different materials. Why does it have such a design?
inner wires
outer jacket
If you find the cable broken, stop using the appliance at once to prevent electric shocks. Tell an adult about it.
Activity Booklet 24 2. What is the relationship between the design of the cable and the electrical conductivity of materials? Work in groups to do a test with the objects on page 32 (part 2). Analyse the electrical conductivity of metals and non-metals to find the answer.
dry battery
Experiments involving electricity can be dangerous. Do them only when an adult is present!
battery holder
light bulb with a holder
wires with crocodile clips
Metals can / cannot conduct electricity. They are electrical conductors. Most non-metals can / cannot conduct electricity. They are insulators. Quick Check
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