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Topic Temperature scales
Asked 7 times across 5 UPSC exams over 32 years (1993–2025), peaking in 1993.
Key insights
- Most tested in CDS — 3 of 7 PYQs
- Most asked in 1993
- Recurs across 7 years (1993–2025)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CSE 1993 → CAPF 2014 → CDS 2018 → NDA 2021 → GEO 2025
How the concept evolved
Rising — more than half its appearances (5 of 7) are since 2016.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
GEO2025
Match List-I with List-II and select the correct answer using the code given below the Lists
| List I (Phenomenon) | List II (Approximate temperature) |
|---|
| A. The freezing point of benzene | 1. 300 K |
| B. The room temperature | 2. 600 K |
| C. The normal human body temperature | 3. 279 K |
| D. The melting point of lead | 4. 310 K |
Codes:
- A A-3 B-4 C-1 D-2
- B A-2 B-1 C-4 D-3
- C A-2 B-4 C-1 D-3
- D A-3 B-1 C-4 D-2 ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
CDS2023
Which one of the following is the correct relation between Celsius and Fahrenheit temperature scales ? (Symbols carry their usual meanings)
- A TF = (10/3)TC + 32
- B TF = (5/9)TC + 36
- C TF = (9/5)TC + 36
- D TF = (9/5)TC + 32 ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
NDA2021
Numerically two thermometers, one in Fahrenheit scale and another in Celsius scale shall read same at
- A – 40° ✓
- B 0°
- C – 273°
- D 100°
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
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