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Topic Resistivity
Asked 5 times across 3 UPSC exams over 11 years (2015–2026), peaking in 2023.
Key insights
- Most tested in CDS — 2 of 5 PYQs
- Most asked in 2023
- Recurs across 4 years (2015–2026)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CDS 2015 → NDA 2023 → GEO 2023
How the concept evolved
Rising — more than half its appearances (4 of 5) are since 2016.
Related concepts
Ideas UPSC tests alongside this one — keep exploring.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
NDA2026
Three wires each of length L, cross-sectional area A and resistivity ρ are connected as shown in the figure. These are to be replaced by another wire of same resistivity with length, cross-sectional area A. If L₁ is the length and A₁ is the cross-sectional area of the new wire, then which one among the following is correct (resistance between points X and Z does not change)?
- A L₁ = 3L and A₁ = 2A ✓
- B L₁ = L and A₁ = A
- C L₁ = 2L and A₁ = 3A
- D L₁ = 2L and A₁ = 2A
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
NDA2023
Which of the following statements are correct about the electrical resistance and resistivity of a wire ?
- Both quantities depend on the area of cross-section of the wire
- Both depend on the temperature
- Resistance of the wire is directly proportional to the resistivity of the wire
- Resistivity of the wire is directly proportional to the length of the wire
Select the correct answer using the code given below :
- A 1 and 2
- B 1 and 3
- C 2 and 3 ✓
- D 2 and 4
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
GEO2023
Which one of the following schematic graphs correctly represents qualitatively the variation of resistivity ρ with respect to temperature T for a semiconductor?
- A graph (a)
- B graph (b)
- C graph (c)
- D graph (d) ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
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