Question

Find the resistance of wire whose thickness is 0.4mm ad length 2m.Given the resistivity of the metal is 8×10power-8Ωm

Answer 1

Answer:

Resistance= (rho x length) /Area of cross section

= (8x10⁻⁸ x 2)/π x 4 x 10⁻⁴ x 10⁻⁴

=16/4π

=4/π

=14/11

Now, you can do calculation on your own

Answer 2

Answer:

1.27 Ω

Explanation:

given:-

p (rho) = 8×10^-8 Ωm

l = 2m

thickness= diameter = 0.4mm

r = 0.2mm = 0.0002m

A = π r²

= 3.14 × 0.0002²

= 1.256×10^-7 m²

R = ?

R = p l/A

R = 8×10^-8 × 2

1.256×10^-6

R = 1.27 Ω