The resistance of a wire of length 100 cm and uniform area of cross-section 0.020 sq.cm, is found to be 2.0 ohm. Calculate specific resistance of wire. plz help me in this question give step by step explanation About the author Everleigh
Answer :- Specific resistance/resistivity of the wire is 4 × 10⁻⁶ Ωm . Explanation :- We have :- → Length of the wire = 100 cm = 1 m → Area of cross section = 0.02 cm² → Resistance = 2 Ω ________________________________ Firstly, let’s convert the area of cross section of the wire from cm² to m² . ⇒ 1 cm² = 10⁻⁴ m² ⇒ 0.02 cm² = 0.02 × 10⁻⁴ m² ⇒ 2 × 10⁻⁶ m² ________________________________ Now, we know that :- R = ρl/A Where :- • R is resistance. • ρ is specific resistance. • l is length of the wire. • A is area of cross section. Substituting values, we get :- ⇒ 2 = (ρ × 1)/2 × 10⁻⁶ ⇒ ρ = 2 × 2 × 10⁻⁶ ⇒ ρ = 4 × 10⁻⁶ Ωm Reply
I=100cm=1m area=0.02=0.000002m^2 specific resistance (Rxarea)/length 2×0.000002×1 =4×10^-6ohm-m Reply
Answer :-
Specific resistance/resistivity of the wire is 4 × 10⁻⁶ Ωm .
Explanation :-
We have :-
→ Length of the wire = 100 cm = 1 m
→ Area of cross section = 0.02 cm²
→ Resistance = 2 Ω
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Firstly, let’s convert the area of cross section of the wire from cm² to m² .
⇒ 1 cm² = 10⁻⁴ m²
⇒ 0.02 cm² = 0.02 × 10⁻⁴ m²
⇒ 2 × 10⁻⁶ m²
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Now, we know that :-
R = ρl/A
Where :-
• R is resistance.
• ρ is specific resistance.
• l is length of the wire.
• A is area of cross section.
Substituting values, we get :-
⇒ 2 = (ρ × 1)/2 × 10⁻⁶
⇒ ρ = 2 × 2 × 10⁻⁶
⇒ ρ = 4 × 10⁻⁶ Ωm
I=100cm=1m
area=0.02=0.000002m^2
specific resistance (Rxarea)/length
2×0.000002×1
=4×10^-6ohm-m