4. If the length of a given conducting wire is
kept constant and its diameter is doubled.
what will be the resistance of the new wire?
Answers
Answered by
5
Answer:
decreases 4 times
Explanation:
The resistance of a conductor of length L and diameter d is given by
R= ρL/π(d/2)²
where ρ= resistivity of material of conductor.
When diameter is doubled, the resistance becomes
R = ρL/π(2d/2)²
=R/4
Answered by
10
Physics
Current Electricity
Answer :
Diameter of wire is doubled.
(length is kept constant)
We have to find the resistance of new wire
⧪ Resistance of conductor is directly proportional to the length of conductor and inversely proportional to the area of cross section of conductor.
Mathematically, R ∝ L/A (A = πr²)
ATQ, length of conductor remains constant.
Therefore, R ∝ 1/(r²)
➙ R/R' = r'²/r²
➙ R/R' = (d'/2)²/(d/2)²
➙ R/R' = d'²/d²
➙ R/R' = (2d)²/d²
➙ R/R' = 4
➙ R' = R/4
Cheers!
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