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प्रश्न
Find the odd one out and give its explanation.
विकल्प
Tungsten
Nichrome
Aluminium
Iron
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उत्तर
Nichrome
Explanation-
Nichrome is an alloy used for making wires, while others are soft metals.
APPEARS IN
संबंधित प्रश्न
Compute the heat generated while transferring 96000 coulomb of charge in one hour through a potential difference of 50 V.
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How does the resistance of a wire vary with its:
diameter?
A heating coil has a resistance of 200 Ω. At what rate will heat be produced in it when a current of 2.5 A flows through it?
Name the material which is used for making the filaments of an electric bulb.
Which of the following characteristic is not suitable for a fuse wire?
(a) thin and short
(b) thick and short
(c) low melting point
(d) higher resistance than rest of wiring
If the current flowing through a fixed resistor is halved, the heat produced in it will become:
How does the wire in the filament of a light bulb behave differently to the other wires in the circuit when the current flows?
What property of the filament wire accounts for this difference?
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Give a scientific reason.
Tungsten metal is used to make a solenoid type coil in an electric bulb.
Identify the figure and give its use.
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what is the heating effect of the electric current? state any four applications of it?
Compute the heat generated while transferring 96000 coulombs of charge in two hours through a potential difference of 40 V.
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Live wire and neutral wires have a 220 V potential difference.
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It would cost a man Rs. 3.50 to buy 1.0 kW h of electrical energy from the Main Electricity Board. His generator has a maximum power of 2.0 kW. The generator produces energy at this maximum power for 3 hours. Calculate how much it would cost to buy the same amount of energy from the Main Electricity Board.
The following is not a safety device.
Explain why fuse wire is always connected in a series arrangement.
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In the electric equipment producing heat like iron, electric heater, boiler, toaster etc., an alloy such as nichrome is used, not pure metals.
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Anannya responded to the question: Why do electrical appliances with metallic bodies are connected to the mains through a three-pin plug, whereas an electric bulb can be connected with a two-pin plug?
She wrote: Three-pin connections reduce heating of connecting wires.
- Is her answer correct or incorrect? Justify.
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