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प्रश्न
Which metal is used to make the filament of an electric bulb?
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उत्तर
Tungsten metal is used to make the filament of an electric bulb.
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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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(b) temperature of the resistor
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(a) chemical effect of current
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(c) lighting effect of current
(d) heating effect of current
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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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What property of the filament wire accounts for this difference?
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(b) Is it safe to handle the bulb when the switch is OFF?
(c) Give a reason for your answer in (b).
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Unscramble the following words:
SFEU
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Write an expression for the amount of heat produced in a resistor when an electric current is passed through it stating the meanings of the symbols used.
The graph of voltage vs current for four different materials is shown below.
Which of these four materials would be used for making filament of bulb?
