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प्रश्न
What is Resistivity?
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उत्तर
The resistivity of a conductor is defined as the resistance of a conductor of unit length and unit area of cross-section.
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संबंधित प्रश्न
Is Ohm’s law universally applicable for all conducting elements? If not, give examples of elements which do not obey Ohm’s law.
Write the formula of resistivity
Write the SI unit of resistivity
Calculate the current flowing through a wire of resistance 5 Ω connected to a battery of potential difference 3 V.
A wire of resistance 3 ohm and length 10 cm is stretched to length 30 cm. Assuming that it has a uniform cross section, what will be its new resistance?
A wire of resistance 9 ohm having length 30 cm is tripled on itself. What is its new resistance?
How would you connect two resistors in series? Draw a diagram. Calculate the total equivalent resistance.
Show by a diagram how two resistors R1 and R2 are joined in parallel. Obtain an expression for the total resistance of the combination.
Fig. represents the circuit used for the verification of Ohm's law. Label the parts from A to F. state the function of each.
- 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) ?
What are ohmic conductors? Give one exmaple. Draw a graph showing the current-voltage relationship for an ohmic conductor.
What are non-ohmic conductors? Give one exmaple. Draw a current-voltage graph for a non-ohmic conductor.
What is ohmic device?
The resistance of a nichrome wire at 0°C is 10Ω. If its temperature coefficient of resistivity of nichrome is 0.004/ °C, find its resistance of the wire at boiling point of water. Comment on the result.
Ohm's law deals with the relationship between ______
State Ohm's Law. Represent it mathematically.
Let the resistance of an electrical device remain constant, while the potential difference across its two ends decreases to one fourth of its initial value. What change will occur in the current through it? State the law which helps us in solving the above stated question.
