Calculate the resistance of the wire of length 10cm and area of cross section 2x10^-4 m2 given the resistivity of the wire 2.82x10^-8 ohm-m .Identify whether the wire is a conductor or insulator?
Answers
Explanation:
Answer:
The resistance of the metal wire is \bold{3.61 \times 10^{-2}}3.61×10−2
Explanation:
Given:
Length of metal wire = 2m
Area of cross section = 1.55 \times 10^{-6} m^{2}1.55×10−6m2
Resistivity of metal = 2.8 \times 10^{-8} \text { ohm } \mathrm{m}2.8×10−8 ohm m
We have to find the resistance of metal wire.
L=2m
A= 1.55 \times 10^{-6} m^{2}1.55×10−6m2
\bold{\rho=\frac{R A}{L}}ρ=LRA
Therefore,
\bold{\mathrm{R}=\frac{\rho L}{A}}R=AρL
Now, let us substitute all the known values in the above expression.
We get,
R=\frac{2.8 \times 10^{-8} \times 2}{1.55 \times 10^{-6}}R=1.55×10−62.8×10−8×2
By simplification we get the above expression as,
\begin{gathered}\begin{array}{l}{R=\frac{560}{1.55 \times 10^{-2}}} \\ {R=3.61 \times 10^{-2}}\end{array}\end{gathered}R=1.55×10−2560R=3.61×10−2
Hence resistance of the metal wire= 3.61 \times 10^{-2}3.61×10−2