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Electrical Power and Household Circuits — Physics STD 10 — Question

ICSE BoardEnglish MediumSTD 10PhysicsElectrical Power and Household Circuits5 Marks
Question
State two circumstances when one may get an electric shock from an electrical gadget. What preventive measure must be provided with the gadget to avoid it?
✓

Answer

One may get an electric shock from an electrical gadget in the following two cases:
(i) If the fuse is put in the neutral wire instead of live wire and due to fault, if an excessive current flows in the circuit, the fuse burns, current stops flowing in the circuit but the appliance remains connected to the high potential point of the supply through the live wire. In this situation, if a person touches the faulty appliance, he may get an electric shock as the person will come in contact with the live wire through the appliance.
Preventive measure: The fuse must always be connected in the live wire.
(ii) When the live wire of a faulty appliance comes in direct contact with its metallic case due to break of insulation after constant use (or otherwise), the appliance acquires the high potential of the live wire. A person touching it will get a shock because current flows through his body to earth.
Preventive measure: Proper 'earthing' of the electric appliance should be done.

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