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प्रश्न
Write scientific reason.
A coil made up of alloy Nichrome is used in the electric heater cooker as a resistor.
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उत्तर
- The electric heater-cooker works on the principle of heating effect of electric current.
- Alloys (such as nichrome) as compared to metals have higher resistivity.
- Unlike metals they can be heated to higher temperature.
Hence, a coil made up of alloy nichrome is used in the electric heater-cooker as a resistor.
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संबंधित प्रश्न
An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.
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(a) tungsten
(b) bronze
(c) nichrome
(d) argon
The electrical resistivities of four materials P, Q, R and S are given below:
| P | `6.84xx10^8`Ωm |
| Q | `1.70xx10^8`Ωm |
| R | ` 1.0xx10^15`Ωm |
| s | `11.0xx10^-7`Ωm |
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| Student | Object | Mass of Object before Rusting in g |
Mass of the coated object in g |
| A | Nail | 3.0 | 3.15 |
| B | Thin plate | 6.0 | 6.33 |
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