What does Dual Nature of Matter and Radiation cover for NEET Physics?

5 lessons: Einstein Photoelectric Equation, Hertz Lenard Observations, Matter Waves, Particle Nature Light and Photoelectric Effect.

How often has Dual Nature of Matter and Radiation come up in NEET past papers?

Our set of verified past papers has 11 questions from this unit, from NEET 2020, 2022, 2023, 2024, 2025 and 2026. Each is answered against the official NTA key.

Is the Dual Nature of Matter and Radiation material free?

Yes. All 5 lessons and 40 practice questions are free, with no login needed.

Dual Nature of Matter and Radiation

5 lessons

Topic index in NCERT order

5 of 5 lessons by the NCERT chapter they teach from, in book order. The page is the first printed page of your NCERT book the lesson cites; PYQs are the past NEET questions on that topic.

Class 12 Physics, Chapter 11

Hertz Lenard Observationsp. 2760 PYQs
Photoelectric Effectp. 2766 PYQs
Einstein Photoelectric Equationp. 2790 PYQs
Matter Wavesp. 2854 PYQs
Particle Nature Lightp. 2851 PYQ

Einstein Photoelectric Equation

8 MCQs1 revision cardWorked example

Easy Recall (2)Direct Application (2)Concept Trap (2)Calculation (2)

Hertz Lenard Observations

8 MCQsWorked example

Easy Recall (3)Direct Application (3)Concept Trap (2)

Matter Waves

8 MCQs4 PYQs3 revision cardsWorked example

Easy Recall (2)Direct Application (2)Concept Trap (2)Calculation (2)

Particle Nature Light

8 MCQs1 PYQs1 revision cardWorked example

Easy Recall (3)Direct Application (3)Calculation (1)Concept Trap (1)

Photoelectric Effect

8 MCQs6 PYQs1 revision cardWorked example

Easy Recall (3)Direct Application (3)Concept Trap (1)Calculation (1)

Past-paper questions from this unit

11 questions from NEET 2020, 2022, 2023, 2024, 2025, 2026. Answers verified against NTA official keys.

By year in our set: 2020 (3) · 2022 (1) · 2023 (1) · 2024 (1) · 2025 (2) · 2026 (3)

Lesson: Photoelectric Effect

NEET 2026

A beam of light falls on a metal surface such that photo-electrons are generated. If power of the light source starts to decrease linearly with time t, then variation of the photocurrent I and magnitude of the stopping potential |V| with time is best represented by :

NTA Answer: Option 1(final)

Report an error · Every fix is public: corrections log

Lesson: Photoelectric Effect

NEET 2026

A ray of light with wavelength λ is incident on three different photo-electric cells namely 1, 2 and 3. The threshold wavelength of these photo-electric cells are λ₁, λ₂ and λ₃, respectively and the magnitude of stopping potentials of these cells are V₁, V₂ and V₃, respectively. The relation between λ and threshold wavelengths are λ₁ < λ, λ₂ > λ and λ₃ >> λ. The correct option is :

1V₁ = 0, V₂ < V₃

2V₁ = 0, V₂ > V₃

3V₁ > V₂, V₃ = 0

4V₁ < V₂, V₃ = 0

NTA Answer: Option 1(final)

Report an error · Every fix is public: corrections log

Lesson: Matter Waves

NEET 2026

A 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 p_Ph, p_e/p_Ph, is : (Take speed of light = 3 × 10⁸ ms⁻¹, charge of electron = −1.6 × 10⁻¹⁹ C and mass of electron = 9 × 10⁻³¹ kg)

12/450

21/250

3225

4275

NTA Answer: Option 3(final)

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Lesson: Matter Waves

NEET 2025

De-Broglie wavelength of an electron orbiting in the n = 2 state of hydrogen atom is close to (Given Bohr radius = 0.052 nm)

12.67 nm

20.067 nm

30.67 nm

41.67 nm

NTA Answer: Option 3(final)

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Lesson: Matter Waves

NEET 2025

A photon and an electron (mass m) have the same energy E. The ratio (λ_photon/λ_electron) of their de Broglie wavelengths is: (c is the speed of light)

1(1/c)√(E/2m)

2√(E/2m)

3c√(2mE)

4c√(2m/E)

NTA Answer: Option 4(final)

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Lesson: Particle Nature Light

NEET 2024Revised key

If 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 E = hν. B. The velocity of a photon is c. C. The momentum of a photon, . ℎ𝜈𝜈 D. In a photon-electron collision,𝑝𝑝 b=oth𝑐𝑐 total energy and total momentum are conserved. E. Photon possesses positive charge. Choose the correct answer from the options given below:

1A and B only

2A, B, C and D only

3A, C and D only

4A, B, D and E only

NTA Answer: Option 2(revised_final)

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Lesson: Photoelectric Effect

NEET 2023

The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are 2.14 eV, 2.30 eV and 2.75 eV respectively. If incident electromagnetic radiation has an incident energy of 2.20 eV, which of these photosensitive surfaces may emit photoelectrons?

1Both Na and K

2K only

3Na only

4Cs only

NTA Answer: Option 4(final)

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Lesson: Photoelectric Effect

NEET 2022

When two monochromatic lights of frequency, ν and ν/2 are incident on a photoelectric metal, their stopping potential becomes V_s/2 and V_s respectively. The threshold frequency for this metal is

1(3/2)ν

22ν

33ν

4(2/3)ν

NTA Answer: Option 1(final)

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Lesson: Photoelectric Effect

NEET 2020

Light with an average flux of 20 W/cm² falls on a non-reflecting surface at normal incidence having surface area 20 cm². The energy received by the surface during time span of 1 minute is :

148 × 10³ J

210 × 10³ J

312 × 10³ J

424 × 10³ J

NTA Answer: Option 4(final)

Report an error · Every fix is public: corrections log

Lesson: Matter Waves

NEET 2020

An electron is accelerated from rest through a potential difference of V volt. If the de Broglie wavelength of the electron is 1.227×10⁻² nm, the potential difference is :

1104 V

210 V

3102 V

4103 V

NTA Answer: Option 1(final)

Report an error · Every fix is public: corrections log

Lesson: Photoelectric Effect

NEET 2020

Light of frequency 1.5 times the threshold frequency is incident on a photosensitive material. What will be the photoelectric current if the frequency is halved and intensity is doubled ?

1zero

2doubled

3four times

4one-fourth

NTA Answer: Option 1(final)

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Exam traps and common mistakes in this unit

Lesson: Einstein Photoelectric Equation

Trap

Photoelectric: dropping work function

Category: Similar Terms

Student writes K_max = hν (forgets W). For frequencies above threshold, K_max = hν − W; W is non-zero.

When it triggers

Photoelectric question with given metal work function or threshold frequency.

How to avoid

Always: K_max = hν − W. If asked for stopping potential V_0: eV_0 = K_max = hν − W.

Lesson: Einstein Photoelectric Equation

Mistake

Forgets work function term in Einstein equation: writes K_max = hν.

Root cause: formula misuse

Correction

Always K_max = hν - W. Above threshold (ν > ν_0 = W/h), photons can eject electrons; their max KE equals photon energy minus W (energy needed to free them).

Formulas in this unit

Lesson: Einstein Photoelectric Equation

Einstein's photoelectric equation

K_{max} = h ν - W

Maximum kinetic energy of photoelectron equals photon energy minus work function. Stopping potential V0 satisfies eV0 = K_max.

Symbol	Quantity	SI Unit
K_max	max KE	J
h	Planck constant	J*s
nu	photon freq	Hz
W	work function	J
V0	stopping potential	V
e	electron charge	C

Valid when

nu > nu_threshold = W/h (else no emission)
One-photon absorption

Lesson: Matter Waves

de Broglie wavelength

λ = \frac{h}{p}

Wavelength associated with any moving particle of momentum p. For electron through V volts: lambda ~ 12.27/sqrt(V) angstroms.

Symbol	Quantity	SI Unit
lambda	de Broglie wavelength	m
h	Planck constant	J*s
p	momentum	kg*m/s
m	mass	kg
v	speed	m/s

Valid when

Non-relativistic (v << c)

Lesson: Particle Nature Light

Photon energy and momentum

E = h ν = \frac{h c}{λ}; p = \frac{h}{λ}

Energy and momentum of a photon. h = 6.626e-34 J*s.

Symbol	Quantity	SI Unit
E	energy	J
nu	frequency	Hz
lambda	wavelength	m
p	momentum	kg*m/s
h	Planck constant	J*s

Valid when

Vacuum (c=speed of light)
Photon = EM quantum

NEET question patterns in this unit

Lesson: Einstein Photoelectric Equation

Einstein eq: K_max = hν - W. Find threshold, work function, or stopping potential.

Multi StepMedium

Common distractors

forgets work function

Uses K_max = hν directly

Lesson: Matter Waves

de Broglie wavelength λ = h/p. For electron through V volts: λ = 12.27/sqrt(V) Å.

Direct ApplicationEasy

Common distractors

misses relativistic correction

Applies non-relativistic when v ~ c

Questions about this unit

What does Dual Nature of Matter and Radiation cover for NEET Physics?: 5 lessons: Einstein Photoelectric Equation, Hertz Lenard Observations, Matter Waves, Particle Nature Light and Photoelectric Effect.
How often has Dual Nature of Matter and Radiation come up in NEET past papers?: Our set of verified past papers has 11 questions from this unit, from NEET 2020, 2022, 2023, 2024, 2025 and 2026. Each is answered against the official NTA key.
Is the Dual Nature of Matter and Radiation material free?: Yes. All 5 lessons and 40 practice questions are free, with no login needed.