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प्रश्न
Name the material which is used for making the heating element of an electric iron.
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उत्तर
The coils of the heating element of an electric iron is made of alloys like nichrome because alloys have a high resistance and a high melting point.
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संबंधित प्रश्न
Complete the following :-
(a)
Find the expression for resistors connected in series.
(i) Two sets A and B, of three bulbs each, are glowing in two separate rooms. When one of the bulbs in set A is fused, the other two bulbs also cease to glow. But in set B, when one bulb fuses, the other two bulbs continue to glow. Explain why this phenomenon occurs.
(ii) Why do we prefer arrangements of Set B for house circuiting?
An electrical appliance has a resistance of 25 Ω. When this electrical appliance is connected to a 230 V supply line, the current passing through it will be:
(a) 0.92 A
(b) 2.9 A
(c) 9.2 A
(d) 92 A
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- in series and
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