COMEDK · Physics · 19. Current Electricity
Two copper wires, one of length \(1 \mathrm{~m}\) and the other of length \(9 \mathrm{~m}\) have the same resistance. The diameters are in the ratio
- A \(3: 1\)
- B \(1: 3\)
- C \(9: 1\)
- D \(1: 9\)
Answer & Solution
Correct Answer
(B) \(1: 3\)
Step-by-step Solution
Detailed explanation
For first copper wire, \[ l_{1}=1 \mathrm{~m} \] For second copper wire, \(l_{2}=9 \mathrm{~m}\) We have to find, diameter ratio of two wires, i.e. \(\frac{d_{1}}{d_{2}}=\) ? Since, both copper wires have same resistances. i.e. \(\quad R_{1}=R_{2}\)…
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