NEET UG · Physics · Units and Measurements

Units and Dimensions: NEET previous year questions

20 questions in ten years of NEET, in 10 of 10 papers. Pattern: Every year. Here is how it is asked and which ideas come back.

Asked in 10 years: 20; about 1.9 per paper
Years asked: 10/10; last asked 2026
Chance of a question next paper: 84%; historical rate, how we compute it
Weighted estimate: 1.9; model; history: 1.9 a paper on average, typically 1–3

Key findings

01
Asked in 10 of 10 papers, 20 questions in all: #13 of 204 topics by ten-year total.
02
79% of its questions since 2018 tested an idea never asked before; none repeated an idea from the year before.
03
The most repeated idea is Error Propagation in Power Functions, asked 3 times (2019, 2023, 2025), usually as “numerical”.
04
NEET has asked 16 of the 86 ideas in this topic; 67 have never been asked, directly or indirectly.
05
Mostly asked as one-line MCQ (50%); 55% easy, 0% hard.

Questions per year

Up to 2023: 1.9; per paper
Since 2024: 1.9; 0.0
Usual gap: 1.0 yrs; between papers asking it
Swing: ±0.8; questions, year to year

Recent framings

dimension of physical quantity
numerical: percentage error in derived quantity
numerical: vernier reading with zero error

Revise first

Error Propagation in Power Functions (2019 2023 2025); Dimensions of Thermal Quantities (2026); Dimensionless Physical Quantities (2022 2024)

How it is asked

Difficulty, format and skill

Across all 20 questions on Units and Dimensions since 2017.

Difficulty

QUESTIONS

119

Easy11 · 55%
Medium9 · 45%
Hard0 · 0%

Format

One-line MCQ · 10 Q50%
Numerical · 10 Q50%

Skill tested

Calculation · 12 Q60%
Recall · 5 Q25%
Multi-step · 2 Q10%
Application · 1 Q5%

Repeats

New idea, or one asked before?

Each column is a paper. Blue questions tested an idea NEET had not asked before; navy ones went back to an idea from an earlier paper. 2017 is the first paper, so everything in it counts as new.

’17’18’19’20’21’22’23’24’25’26

Idea asked for the first time
Idea asked in an earlier paper

Coverage of the topic

NEET has asked 16 of the 86 ideas in this topic. 67 have never been asked yet.

1667

Asked directly16 · 19%
Touched inside another question3 · 3%
Never asked67 · 78%

Ideas come from Lumi’s syllabus map of NCERT. A never-asked idea is not a safe skip: most new questions come from exactly these.

Drill down

Idea, year, question

Every idea NEET tested in this topic, with its ten papers. Open one to read the questions.

ideaAskedShareYears’17’18’19’20’21’22’23’24’25’26

Repeated3 · 15%15%3/10
- 2025 · Q42
  A physical quantity $P$ is related to four observations $a$ , $b$ , $c$ and $d$ as follows: $P = a^3b^2/c\sqrt{d}$ The percentage errors of…
  easyNumerical
- 2023 · Q7
  A metal wire has mass $(0.4\pm0.002)$ g, radius $(0.3\pm0.001)$ mm and length $(5\pm0.02)$ cm. The maximum possible percentage error in…
  mediumNumerical
- 2019 · Q44
  In an experiment, the percentage of error occurred in the measurement of physical quantities A, B, C and D are 1%, 2%, 3% and 4%…
  easyNumericalNew idea
Repeated2 · 10%10%2/10
Repeated2 · 10%10%2/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10
1 · 5%5%1/10

Squares are the ten papers, 2017 to 2026; darker means more questions. Share is of the level above.

Ideas

Every idea inside this topic

16 different ideas were tested; 3 came more than once. Dimensional Formulas is the foundation for 35 other ideas in the syllabus.

Error Propagation in Power Functions3×
numerical
Numerical · 6% next · foundation for 1
Dimensionless Physical Quantities2×
units and dimensions of angle quantities
One-line MCQ · 6% next
Dimensions of Universal Constants2×
dimension of physical quantity
One-line MCQ · 4% next · foundation for 1
Dimensions of Thermal Quantities1×
dimension of physical quantity
One-line MCQ · 6% next
Vernier Caliper Reading and Zero Error1×
numerical
Numerical · 6% next · foundation for 3
Principle of Homogeneity1×
dimensionless combination of constants
One-line MCQ · 6% next · foundation for 11
Vernier Caliper Least Count1×
numerical
Numerical · 6% next · foundation for 5
Systematic vs Random Errors1×
identify type of measurement error
One-line MCQ · 4% next
Dimensions of Electrical Quantities1×
dimension of physical quantity
One-line MCQ · 4% next · foundation for 1
Significant Figures in Multiplication and Division1×
significant figures in multiplication
Numerical · 4% next
Dimensional Formulas1×
dimension of quantity with unusual fundamental set
One-line MCQ · 4% next · foundation for 35
Screw Gauge Measurements1×
numerical
Numerical · 4% next · foundation for 1
Dimensions of Pressure and Energy Density1×
dimension of physical quantity
One-line MCQ · 4% next
Screw Gauge Pitch and Least Count1×
numerical
Numerical · 4% next · foundation for 5
Significant Figures in Addition and Subtraction1×
significant figures in subtraction
Numerical · 4% next
Screw Gauge Reading and Zero Error1×
numerical
Numerical · 4% next · foundation for 4

Idea	Times	Format	Chance next	Foundation for
Error Propagation in Power Functionsnumerical	3	NumericalCalculation	6%	1 ideas
Dimensionless Physical Quantitiesunits and dimensions of angle quantities	2	One-line MCQRecall	6%	–
Dimensions of Universal Constantsdimension of physical quantity	2	One-line MCQCalculation	4%	1 ideas
Dimensions of Thermal Quantitiesdimension of physical quantity	1	One-line MCQMulti-step	6%	–
Vernier Caliper Reading and Zero Errornumerical	1	NumericalCalculation	6%	3 ideas
Principle of Homogeneitydimensionless combination of constants	1	One-line MCQApplication	6%	11 ideas
Vernier Caliper Least Countnumerical	1	NumericalCalculation	6%	5 ideas
Systematic vs Random Errorsidentify type of measurement error	1	One-line MCQRecall	4%	–
Dimensions of Electrical Quantitiesdimension of physical quantity	1	One-line MCQRecall	4%	1 ideas
Significant Figures in Multiplication and Divisionsignificant figures in multiplication	1	NumericalCalculation	4%	–
Dimensional Formulasdimension of quantity with unusual fundamental set	1	One-line MCQCalculation	4%	35 ideas
Screw Gauge Measurementsnumerical	1	NumericalCalculation	4%	1 ideas
Dimensions of Pressure and Energy Densitydimension of physical quantity	1	One-line MCQRecall	4%	–
Screw Gauge Pitch and Least Countnumerical	1	NumericalCalculation	4%	5 ideas
Significant Figures in Addition and Subtractionsignificant figures in subtraction	1	NumericalCalculation	4%	–
Screw Gauge Reading and Zero Errornumerical	1	NumericalCalculation	4%	4 ideas

Chance next is the historical rate at which an idea with this record came back in the following paper. It is low for every idea, which is why learning the topic beats memorising past questions. All repeated ideas

Every question

Units and Dimensions questions, year by year

The opening words of each question as it appeared in the official paper, with the idea it tested.

NEET 20261 question

Q37
Consider that $\sigma_s$ , $k_B$ , b represent Stefan-Boltzmann constant, Boltzmann constant and Wien's displacement law constant,…
Idea: Dimensions of Thermal Quantities
New ideaMediumOne-line MCQ

NEET 20252 questions

Q25
Consider the diameter of a spherical object being measured with the help of a Vernier callipers. Suppose its 10 Vernier Scale Divisions…
Idea: Vernier Caliper Reading and Zero Error
New ideaEasyNumerical
Q42
A physical quantity $P$ is related to four observations $a$ , $b$ , $c$ and $d$ as follows: $P = a^3b^2/c\sqrt{d}$ The percentage errors of…
Idea: Error Propagation in Power Functions
EasyNumerical

NEET 20243 questions

Q17
The quantities which have the same dimensions as those of solid angle are :
Idea: Dimensionless Physical Quantities
EasyOne-line MCQ
Q18
In a vernier calipers, $(N + 1)$ divisions of vernier scale coincide with $N$ divisions of main scale. If 1 MSD represents 0.1 mm, the…
Idea: Vernier Caliper Least Count
New ideaMediumNumerical
Q37
A force defined by $F = \alpha t^2 + \beta t$ acts on a particle at a given time $t$ . The factor which is dimensionless, if $\alpha$ and…
Idea: Principle of Homogeneity
New ideaMediumOne-line MCQ

NEET 20232 questions

Q7
A metal wire has mass $(0.4\pm0.002)$ g, radius $(0.3\pm0.001)$ mm and length $(5\pm0.02)$ cm. The maximum possible percentage error in…
Idea: Error Propagation in Power Functions
MediumNumerical
Q23
The errors in the measurement which arise due to unpredictable fluctuations in temperature and voltage supply are :
Idea: Systematic vs Random Errors
New ideaEasyOne-line MCQ

NEET 20223 questions

Q8
Plane angle and solid angle have :
Idea: Dimensionless Physical Quantities
New ideaEasyOne-line MCQ
Q14
The dimensions $[MLT^{-2}A^{-2}]$ belong to the :
Idea: Dimensions of Electrical Quantities
New ideaMediumOne-line MCQ
Q50
The area of a rectangular field (in m $^2$ ) of length 55.3 m and breadth 25 m after rounding off the value for correct significant digits…
Idea: Significant Figures in Multiplication and Division
New ideaEasyNumerical

NEET 20213 questions

Q11
If force [F], acceleration [A] and time [T] are chosen as the fundamental physical quantities. Find the dimensions of energy.
Idea: Dimensional Formulas
New ideaMediumOne-line MCQ
Q19
If E and G respectively denote energy and gravitational constant, then $\frac{E}{G}$ has the dimensions of :
Idea: Dimensions of Universal Constants
MediumOne-line MCQ
Q23
A screw gauge gives the following readings when used to measure the diameter of a wire Main scale reading : 0 mm Circular scale reading :…
Idea: Screw Gauge Measurements
New ideaEasyNumerical

NEET 20203 questions

Q146
A screw gauge has least count of 0.01 mm and there are 50 divisions in its circular scale. The pitch of the screw gauge is :
Idea: Screw Gauge Pitch and Least Count
New ideaEasyNumerical
Q167
Dimensions of stress are :
Idea: Dimensions of Pressure and Energy Density
New ideaEasyOne-line MCQ
Q176
Taking into account of the significant figures, what is the value of 9.99 m $-$ 0.0099 m ?
Idea: Significant Figures in Addition and Subtraction
New ideaEasyNumerical

NEET 20191 question

Q44
In an experiment, the percentage of error occurred in the measurement of physical quantities A, B, C and D are 1%, 2%, 3% and 4%…
Idea: Error Propagation in Power Functions
New ideaEasyNumerical

NEET 20181 question

Q37
A student measured the diameter of a small steel ball using a screw gauge of least count 0.001 cm. The main scale reading is 5 mm and zero…
Idea: Screw Gauge Reading and Zero Error
New ideaMediumNumerical

NEET 20171 question

Q19
A physical quantity of the dimensions of length that can be formed out of c, G and $\frac{e^2}{4\pi\epsilon_0}$ is [c is velocity of…
Idea: Dimensions of Universal Constants
MediumOne-line MCQ

Questions from the official NEET UG papers published by NTA (CBSE before 2019). Topic and idea tags, counts and notes are Lumi’s.