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प्रश्न
Find the odd one out and give its explanation.
पर्याय
Tungsten
Nichrome
Aluminium
Iron
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उत्तर
Nichrome
Explanation-
Nichrome is an alloy used for making wires, while others are soft metals.
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संबंधित प्रश्न
An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.
(b) How much energy is transferred to the heater each second?
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diameter?
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An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.
A resistance of 25 Ω is connected to a 12 V battery. Calculate the heat energy in joules generated per minute.
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(a) thin and short
(b) thick and short
(c) low melting point
(d) higher resistance than rest of wiring
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 |
Which material will you use for making: (a) heating element of electric iron (b) connecting wires of electric iron (c) covering of connecting wires? Give reason for your choice in each case.
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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Three heaters each rated 250 W, 100 V are connected in parallel to a 100 V supply. Calculate:
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- the energy supplied in kWh to the three heaters in 5 hours.
Give a scientific reason.
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Identify the figure and give its use.
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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 |
What might be the reason for the varied observations of the two students?
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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?
