Physics
(a) Define specific resistance.
(b) What happens to the specific resistance of a conductor if its length is doubled?
(c) Name a substance whose specific resistance remains almost unchanged with the increase in its temperature.
Answer
(a) Specific resistance of a material is the resistance of a wire of that material of unit length and unit area of cross section.
(b) Specific resistance of the wire remains unchanged since it does not depend on the dimensions of the wire. It is the characteristic property of the substance.
(c) Manganin.
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