NEET UG · Physics · Class 12

Dual Nature of Radiation and Matter: NEET previous year questions

20 questions in ten years of NEET, asked in 10 of 10 years. Here is what this chapter tests and how.

Asked in 10 years: 20; 10 of 10 papers
10-year average: 1.9; a paper · 2.3 since 2024 +0.5
Typical range: 1–3; questions a paper; fewest 1, most 3
Weighted estimate: 2.2; model, recent papers count more · about 9 marks

Typical range (fact)
10-year average (fact)
Weighted estimate (model)

Typical range: questions per paper in the middle eight of the ten papers, leaving out the single highest and lowest year (about the 10th to 90th percentile), each paper scaled to 180 questions. The ten-year average and the range are historical fact. The weighted estimate is a model: each paper's share, with recent papers counting more (half-life three years), and dropped syllabus removed. It is a guide to effort, not a forecast.

What to do

How to spend time on Dual Nature of Radiation and Matter

Priority

Should do

Among the chapters that took NEET from half to 80% of its questions. How bands are set

Past questions: 20in 10 of 10 papers
Study plan gives it: 17 hover 12 months; 13 h over 6

Study this chapter →Practise →

Ideas asked most often

de Broglie Wavelength of Particles4×
Photon Momentum and Effective Mass3×
Effect of Intensity vs. Frequency2×
Threshold Wavelength Condition2×

72 of the 88 ideas in Lumi’s map of this chapter have not been asked or touched in ten years. New questions often come from ideas like these, so learn the whole chapter, not just the list above.

Questions per year

Kind of question

SHARE OF 10 YEARS

Calculation55%
Figure-based20%
Application15%
Concept10%

Most common asks: numerical (9); effect of frequency and intensity on photocurrent (3); identify metals emitting photoelectrons (1).

Profile

This chapter in numbers

Where it ranks, how steady it is, and what it costs to study.

Rank, all NEET chapters: #36; of 80 by weighted estimate
Rank in Physics: #7; of 27 chapters
Share of the paper: 1.1%; ten-year average
Busiest year: 2020; 3 questions
Year to year: Steady; varies by about 0.6 questions
Long-run direction: +0.11; questions per paper, per year
Easy questions: 45%; 64% of ideas rated hard
With a figure: 20%; graph, diagram or structure
Study time: 17 h; 13 h on a 6-month plan
Marks per study hour: 0.53; #52 of 80 chapters
Foundation for others: 90%; of its ideas are used in other chapters

Difficulty, year by year

Each question rated easy, medium or hard against NCERT.

20171
20182
20191
20203
20212
20222
20232
20242
20252
20263

Easy
Medium
Hard

What it asks you to do

SHARE OF QUESTIONS

Calculation30%
Multi-step25%
Data or graph20%
Application15%
Concept10%

Coverage

How much of the chapter NEET has used

We split the chapter into 88 ideas. In ten years NEET built a question around 11 of them. Most of the chapter has never been asked, which is why learning it whole beats memorising past questions.

Asked as the main idea: 11
Touched on in a question: 5
Never asked: 72

Topics

What repeats, topic by topic

Questions per topic in each year's paper. Topics that come every year are worth learning first.

Photoelectric Effect · Every year20
1213222223

’17’18’19’20’21’22’23’24’25’26

Topic	2017	’18	2019	’20	2021	’22	2023	’24	2025	’26	Total
Photoelectric EffectEvery year	1	2	1	3	2	2	2	2	2	3	20

03+questions in that year’s paper

Photoelectric Effect
Expect a short numerical problem (one or two formula steps, four numeric options) about Photoelectric Effect; a diagram-based item (read or label a figure/graph, then answer) is the next most likely shape. Past framings centre on: numerical; effect of frequency and intensity on photocurrent.

Drill down

Topic, idea, question

Open a topic to see every idea NEET tested inside it, then open an idea to read the questions. Each row shows its ten papers.

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

Open20 · 100%100%10/1023222223
13 ideas inside
- Repeated4 · 20%20%4/10
- Repeated3 · 15%15%3/10
- 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

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

Ideas

The exact ideas NEET has asked

Inside the topics, 13 different ideas were tested. These came more than once, or are new since 2024.

de Broglie Wavelength of Particles4×
numerical
Photon Momentum and Effective MassNew3×
count correct statements on photon properties
Effect of Intensity vs. FrequencyNew2×
effect of frequency and intensity on photocurrent
Threshold Wavelength Condition2×
effect of frequency and intensity on photocurrent

Idea	Times	Usually asked as
de Broglie Wavelength of Particlesnumerical	4	Figure-based
Photon Momentum and Effective Masscount correct statements on photon properties	3	NumericalNew
Effect of Intensity vs. Frequencyeffect of frequency and intensity on photocurrent	2	Figure-basedNew
Threshold Wavelength Conditioneffect of frequency and intensity on photocurrent	2	One-line MCQ

Every question

Dual Nature of Radiation and Matter questions, year by year

The opening words of each question as it appeared in the official paper.

NEET 20263 questions

Q8A beam of light falls on a metal surface such that photo-electrons are generated. If power of the light source starts to decrease linearly…Figure-based · figure
Q18A ray of light with wavelength $\lambda$ is incident on three different photo-electric cells namely 1, 2 and 3. The threshold wavelength…One-line MCQ
Q19A photon and an electron, each of 20 eV energy, move in free space. The ratio of linear momentum of electron $p_e$ to that of photon…Numerical

NEET 20252 questions

Q37A photon and an electron (mass $m$ ) have the same energy $E$ . The ratio ( $\lambda_{photon}/\lambda_{electron}$ ) of their de Broglie…One-line MCQ
Q38Which of the following options represent the variation of photoelectric current with property of light shown on the x-axis? A. [graph:…Figure-based · figure

NEET 20242 questions

Q10If $c$ is the velocity of light in free space, the correct statements about photon among the following are : A. The energy of a photon is…Other
Q34The graph which shows the variation of $\left(\frac{1}{\lambda^2}\right)$ and its kinetic energy, $E$ is (where $\lambda$ is de Broglie…Figure-based · figure

NEET 20232 questions

Q1The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are 2.14 eV, 2.30 eV and 2.75 eV respectively. If incident…One-line MCQ
Q22The minimum wavelength of $X$ -rays produced by an electron accelerated through a potential difference of $V$ volts is proportional to:One-line MCQ

NEET 20222 questions

Q30The graph which shows the variation of the de Broglie wavelength ( $\lambda$ ) of a particle and its associated momentum (p) is :Figure-based · figure
Q31When two monochromatic lights of frequency, $\nu$ and $\frac{\nu}{2}$ are incident on a photoelectric metal, their stopping potential…Numerical

NEET 20212 questions

Q24The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm, when it delivers the…Numerical
Q26An electromagnetic wave of wavelength ' $\lambda$ ' is incident on a photosensitive surface of negligible work function. If 'm' mass is of…One-line MCQ

NEET 20203 questions

Q157Light of frequency 1.5 times the threshold frequency is incident on a photosensitive material. What will be the photoelectric current if…One-line MCQ
Q159The energy required to break one bond in DNA is $10^{-20}$ J. This value in eV is nearly :Numerical
Q175An electron is accelerated from rest through a potential difference of V volt. If the de Broglie wavelength of the electron is…Numerical

NEET 20191 question

Q13An electron is accelerated through a potential difference of 10,000 V. Its de Broglie wavelength is, (nearly) : $(m_e = 9\times10^{-31}$ kg)Numerical

NEET 20182 questions

Q12An electron of mass m with an initial velocity $\vec{V} = V_0\hat{i}$ ( $V_0 > 0$ ) enters an electric field $\vec{E} = -E_0\hat{i}$ ( $E_0$ …Numerical
Q14When the light of frequency $2v_0$ (where $v_0$ is threshold frequency), is incident on a metal plate, the maximum velocity of electrons…Numerical

NEET 20171 question

Q6The de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (Kelvin) and mass m, is :One-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.

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