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प्रश्न
What is a short circuit?
उत्तर
Due to a fault in the equipment or if the plastic coating on the ‘live’ and the ‘neutral’ wires gives away the two wires come in contact with each other and a large current flows through it producing heat. This is known as short circuit.
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संबंधित प्रश्न
Name any two effects of electric current.
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Why are the coils of electric irons and electric toasters made of an alloy rather than a pure metal?
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diameter?
Why does the connecting cord of an electric heater not glow hot while the heating element does?
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Name the material which is used for making the filaments of an electric bulb.
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| P | `6.84xx10^8`Ωm |
| Q | `1.70xx10^8`Ωm |
| R | ` 1.0xx10^15`Ωm |
| s | `11.0xx10^-7`Ωm |
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Give a scientific reason.
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Write the mathematical expression for Joule's law of heating.
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