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What is electrical resistivity ? Derive ...

What is electrical resistivity ? Derive its SI unit, In a series electrical comprising a resistor made up of metallic wire, the ammeter reads , 100 mA. If the length of the wire is doubled, how will the current in the circuit change ? Justify your answer.

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### Step-by-Step Solution 1. **Definition of Electrical Resistivity**: Electrical resistivity (ρ) is defined as the resistance offered by a conductor of length 1 meter and cross-sectional area of 1 square meter. It quantifies how strongly a given material opposes the flow of electric current. 2. **Formula for Electrical Resistivity**: The relationship between resistance (R), resistivity (ρ), length (L), and cross-sectional area (A) of a conductor is given by the formula: \[ ...
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