resistance of a metal wire of length 1m is 26ohm at 20degree Celsius. if the diameter of wire is 0.3mm ,what will be the restivity of the metal at that temperature
Answers
Answered by
3
Resistance , R = 26Ω
Length of wire , L = 1m
diameter of circular part of wire ,d = 0.3mm = 0.3 × 10⁻³m
so, base area of wire , A = πr² = πd²/4 [ ∵d = 2r]
= 3.14 × (0.3 × 10⁻³)²/4m²
= 3.14 × 9 × 10⁻⁸/4 m²
= 28.26/4 × 10⁻⁸ m² = 7.06 × 10⁻⁸ m²
Now, use formula,
R = ρL/A
Here, R is the resistance, ρ is the resistivity , L is the length of wire and A is the base area of it .
So , ρ = RA/L = 26Ω × 7.06 × 10⁻⁸m²/1m
ρ = 1.8356 × 10⁻⁶ Ωm
Hence, resistivity is 1.8356 × 10⁻⁶ Ωm at 20°C
Read more on Brainly.in - https://brainly.in/question/1373897#readmore
Length of wire , L = 1m
diameter of circular part of wire ,d = 0.3mm = 0.3 × 10⁻³m
so, base area of wire , A = πr² = πd²/4 [ ∵d = 2r]
= 3.14 × (0.3 × 10⁻³)²/4m²
= 3.14 × 9 × 10⁻⁸/4 m²
= 28.26/4 × 10⁻⁸ m² = 7.06 × 10⁻⁸ m²
Now, use formula,
R = ρL/A
Here, R is the resistance, ρ is the resistivity , L is the length of wire and A is the base area of it .
So , ρ = RA/L = 26Ω × 7.06 × 10⁻⁸m²/1m
ρ = 1.8356 × 10⁻⁶ Ωm
Hence, resistivity is 1.8356 × 10⁻⁶ Ωm at 20°C
Read more on Brainly.in - https://brainly.in/question/1373897#readmore
Similar questions