copper is a good conductor and thick wires have low resistance
nichrome has a high resistance causing it to heat up without melting
Slide 45
Topic 7 page 35
3. A variable resistor is used to
4. When the volume on a radio is turned Down
5. Cookers need thick cabling
increase and decrease the current by changing the length of a resistance wire
the resistance wire is lengthened, causing a reduction in the current.
because they use much more current than lamps
Slide 46
Topic 7 page 36
The purpose of a fuse is
to protect you from a short circuit - safety
Not to make the device work
Slide 47
(components used in slides)
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