Question

A very small current is sent through a wire of length 15m and cross-sectional area 6x10^-7 m^2.Its resistance is measured to be 5 ohm. Find the specific resistance of the material of the
wire at the temperature of the experiment.
What will be the specific conductance?

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Answer 1

Answer:

Length of the copper wire = 15m (Given)

Cross sectional area of the wire = 6x10^-7 m²(Given)

Resistance = 5 Ώ (Given)

Resistance of a wire is given as = R = ρL/A

where,

ρ is the resistivity, L is the length and A is the area

now, R = 5 ohm ; Length, l = 15m ; A = 6×10^-7m²

Thus, resistivity,

p = RA/L

= 5×6×10^-7/15

or, resistivity , p = 2×10^-7 Ώ

Therefore, the specific conductance is  2×10^-7 Ώ