What will be the resistance of an aluminium wire of length 1.2 m and cross sectional area $2.6 mm^2$. The resistivity of aluminium is $2.6 \times 10^{-8} \Omega m$
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → $1.2 \times 10^{-2} \Omega$
Resistance of an wire (R) -
$R=ρ\frac{L}{A}$
where,
Resistivity $(ρ) = 2.6 × 10^{-8}Ωm$
Length $(l)=1.2m$
Sectional Area $(A) = 2.6mm^2=2.6× 10^{-6}m^2$
$R=\frac{2.6 × 10^{-8} × 1.2}{2.6 × 10^{-6}}$
$=1.2 \times 10^{-2} \Omega$