If the resistivity and cross-sectional area of a metallic wire remain constant, then on increasingits length the resistance of the wire will
Correct answer: A. increase.
- A. increase.
- B. decrease.
- C. become zero.
- D. remain constant.
Explanation
The resistance (R) of a metallic wire is directly proportional to its length (L) and resistivity (ρ), and inversely proportional to its cross-sectional area (A). This relationship is described by the formula:R = ρL/AWhere: * R = Resistance * ρ = Resistivity (a material property) * L = Length * A = Cross-sectional AreaAccording to the question, the resistivity (ρ) and cross-sectional area (A) of the metallic wire remain constant. If you increase the length (L) while ρ and A are held constant, the resistance (R) must also increase, as they are directly proportional.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Resistance and Resistivity
Resistance measures opposition to current in a conductor and follows R = V/I for an ohmic conductor, while resistivity is an intrinsic property of the material. Questions use R = ρL/A, examine effects of length, cross-sectional area and temperature, and distinguish resistance, resistivity, conductance and conductivity.
Practise Current Electricity
1,052 free Current Electricity MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Resistance and Resistivity questions
The unknown resistance of the given Whetstone bridge is
SI unit of resistivity is _
Resistance of a wire is 'R' ohms. The wire is stretched to four times its length, then its resistance in ohms is
The colors of the strips on a certain carbon resistor from left to right are green, black, and blue, respectively. Its resistance is
A 1.0-ton split air conditioner (AC) operates at 220 V and uses 1090 W. The resistance of the air conditioner will be
In a Wheatstone bridge, when the condition R1/R2 = R3/R4 is satisfied, then the current passing through the galvanometer will be