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प्रश्न
Name the unit of electrical resistance and give its symbol.
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उत्तर
The SI unit of electrical resistance is ohm and its symbol is Ω.
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संबंधित प्रश्न
Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?
Is Ohm’s law universally applicable for all conducting elements? If not, give examples of elements which do not obey Ohm’s law.
The relationship between the potential difference and the current in a conductor is stated in the form of a law.
1) Name the law.
2) What does the slope of V-I graph for a conductor represent?
3) Name the material used for making the connecting wire.
Write the formula of resistivity
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(a) one-fourth
(b) four time
(c) half
(d) double
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- Name and state the law which relates the potential difference and current in a conductor.
- What is the necessary condition for a conductor to obey the law named above in part (a) ?
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Draw a neat diagram for the verification of Ohm’s law by voltmeter-ammeter method. By another diagram show the relation between p.d. and current.
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Neglecting internal resistance of the cell use (> or < or =) to compare:
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