JEE Mains · Physics · STD 12 - 3. current electricity
A uniform metallic wire carries a current \(2\,A\). when \(3.4\,V\) battery is connected across it. The mass of uniform metallic wire is \(8.92 \times 10^{-3} \,kg\). density is \(8.92 \times 10^3\,kg / m ^3\) and resistivity is \(1.7 \times 10^{-8} \Omega- m\). The length of wire is \(l=............\,m\)
- A \(6.8\)
- B \(10\)
- C \(5\)
- D \(100\)
Answer & Solution
Correct Answer
(B) \(10\)
Step-by-step Solution
Detailed explanation
\(I =2\,A\) \(\Delta V =3.4\,V\) Using Ohm's Law \(R =\frac{3.4}{2}=1.7 \Omega\) \(1.7=\frac{\rho L }{ A }\) \(L =\frac{1.7( A )}{\rho}\) \(M =(\text { density volume })\) \(Volume =\frac{8.92 \times 10^{-3}}{8.92 \times 10^3}=10^{-6}\)…
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