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प्रश्न
The unit of electrical resistance is:
(a) ampere
(b) volt
(c) coulomb
(d) ohm
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उत्तर
(d) ohm
The unit of electrical resistance is ohm.
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संबंधित प्रश्न
What will be the change in the current if the potential difference is kept constant and the resistance of the circuit is made four times?
- It will remain unchanged.
- It will become four times.
- It will become one-fourth.
- It will become half.
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Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?
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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.
Fill in the following blank with suitable words:
Resistance is measured in .............. The resistance of a wire increases as the length ..............; as the temperature ..............; and as the cross-sectional area .............. .
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The resistivity of copper = 1.7 × 10–8 Ω m
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(i) Metal and
(ii) Semiconductor ?
A metal sphere is kept on an insulting stands. A negatively charged rod is brought near it, then the sphere is earthed as shown. On removing the earthing, and taking the negatively charged rod away, what will be the nature of charge on the sphere? Give reason for your answer.
Tick(✓) the correct choice in the following:
Ohm's law is applicable to
Choose the correct alternative.
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The ratio of the potential difference to the current is known as ________.
Obtain the macroscopic form of Ohm’s law from its microscopic form and discuss its limitation.
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Neglecting internal resistance of the cell use (> or < or =) to compare:
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