| 1. | The heating element of an electric iron is made up of ? | |
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iron
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aluminium
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copper
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nichrome
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Report Question| 2. | A fuse wire repeatedly gets burnt when used with a good heater. It is advised to use a fuse wire of ? | |
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less length
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more radius
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less radius
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more length
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| 3. | If R1 and R2 be the resistance of the filament of 40 W and 60 W respectively operating 220 V, then ? | |
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R1 ? R2
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R1 = R2
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R2 < R1
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R1 < R2
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| 4. | choose the statement which is/ are incorrect ? | |
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In the series connection of electrical appliances, the overall resistance of the circuit increases too much due to which the current from the power supply is low.
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In series circuit, if one electrical appliance stops working due to some defect, then all other appliances also stop working.
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In series circuit, the appliances get the same voltage as that of the power supply line.
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In series circuit, all the electrical appliances have only one switch due to which they cannot be turned on or off separately.
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| 5. | whether the statements are correct or not ? | |
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When the potential difference is halved the current gets doubled.
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When the length of a wire is halved, then its resistance also gets halved.
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A long wire or long conductor has more resistance.
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When the area of cross section of a wire is doubled its resistance gets halved.
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| 6. | The electrical resistance of insulators is ? | |
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zero
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infinitely high
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low
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high
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| 7. | A cooler of 1500 W, 200 volt and a fan of 500 W, 200 volt are to be used from a household supply. The rating of fuse to be used is ? | |
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7.5 A
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10 A
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5.0 A
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2.5 A
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| 8. | The least resistance obtained by using 2 ohm, 4 ohm, 1 ohm and 100 ohm is ? | |
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< 1 ohm
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> 2 ohm
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< 4 ohm
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< 100 ohm
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| 9. | The values of mA and microA are ? | |
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10^–6 and 10^–3 A respectively
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10^–3 and 10^–9 A respectively
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10^–6 and 10^–9 A respectively
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10^–3 and 10^–6 A respectively
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| 10. | The resistance of a resistor is reduced to half of its initial value. In doing so, if other parameters of the circuit remain unchanged, the heating effects in the resistor will become ? | |
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four times
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one-fourth
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half
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two times
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