A conductor has a length equal to pi meters and radius of r meters. Its resistance will be equal to:
Correct answer: B. R = ρ/r2
- A. R = ρ/r1
- B. R = ρ/r2
- C. R = ρ/r3
- D. R = ρ/r4
Explanation
We know that resistance is given by:⇒ R = ρ L / A .........(i)Since, A = π r2 and according to given data, L = πSubstituting the values in equation (i), we get:⇒ R = ρ π / π r2⇒ R = ρ/r2Diagram:
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Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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