Physics
How does (a) resistance, and (b) specific resistance of a wire depend on it's (i) length, and (ii) radius?
Answer
(a) Dependency of resistance of a wire is as follows:
- Resistance of a wire is directly proportional to length of the wire.
- Resistance of a wire is inversely proportional to the square of radius of the wire.
(b) Dependency of specific resistance of a wire is as follows:
- Specific resistance of a wire does not depend on length of the wire as it is a characteristic property of the material of wire.
- Specific resistance of a wire does not depend on radius of the wire as it is a characteristic property of the material of wire.
Related Questions
(a) Name two factors on which the specific resistance of a wire depends?
(b) Two wires A and B are made of copper. The wire A is long and thin while the wire B is short and thick. Which will have more specific resistance?
Name a material which is used for making the standard resistor. Give a reason.
How does the specific resistance of a semi-conductor change with the increase in temperature?
(a) Name the material used for making connection wires. Give reason for your answer.
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