12th Physics Top 50 Most Repeated 2-Mark Questions & 5-Year Question Bank

Preparing for the Class 12 Physics board exam can be daunting, but focusing on high-frequency questions is the smartest way to secure marks. This page features a curated list of the Top 50 most repeated 2-mark questions and a comprehensive collection derived from the last five years of government exam papers—including Mid-terms, Quarterly, Half-yearly, and Public exams.

🎯 The “Must-Study” Top 50 – Two Marks

Number next to questions tells how many times it has been appeared in past few years

Uses Based Questions : 9

1.List out the uses of IR rays / radiation. (any two)(3)

It provides electrical energy to satellites by means of solar cells.
It is used to produce dehydrated fruits,
In green houses to keep the plants warm, heat therapy for muscular pain or sprain,
TV remote as a signal carrier,
To look through haze fog or mist and used in night vision or infrared photography.

2.Give two uses of UV radiation(3)

It is used to destroy bacteria in sterilizing the surgical instruments, burglar alarm, to detect the invisible writing, finger prints and also in the study of atomic structure.

3.What are the uses of X-rays?(1)

X-rays are used extensively in studying structures of inner atomic electron shells and crystal structures.
It is used in detecting fractures, diseased organs, formation of bones and stones, observing the progress of healing bones.
It is used to detect faults, cracks, flaws and holes in a finished metal product.

4.List the uses of Polaroids? (1)

Polaroids are used in goggles and cameras to avoid glare of light.
Polaroids are used to take 3D pictures i.e., holography.
Polaroids are used to improve contrast in old oil paintings.

5.Give two applications of Seebeck effect.(1)

Seebeck effect is used in thermoelectric generators.These thermoelectric generators are used in power plants to convert waste heat into electricity.
Used in automobiles as automotive thermoelectric generators for increasing fuel efficiency.
Used in thermocouples and thermopiles to measure the temperature difference between the two objects.

6.What is corona discharge?(7)

The electric field near the edge of conductor is very high and it ionizes the surrounding air. The positive ions are repelled at the sharp edge and negative ions are attracted towards the sharper edge. This reduces the total charge of the conductor near the sharp edge. This is called action of points or corona discharge.

7.Mention the ways of producing Induced Emf(6)

By changing the magnetic field B
By changing the area A of the coil and
By changing the relative orientation θ of the coil with magnetic field.

Photocell based questions : 6

8.Write the applications of photoelectric cells or photo cell.(3)

Photo cells have many applications, especially as switches and sensors.
Photo cells are used for reproduction of sound in motion pictures
Used as timers to measure the speeds of athletes during a race.

9.What is a photo cell(1)

Photo electric cell or photo cell is a device which converts light energy into electrical energy. It works on the principle of photo electric effect.

10.What is photoelectric effect? (1)

The ejection of electrons from a metal plate when illuminated by light or any other electromagnetic radiation of suitable wavelength (or frequency) is called photoelectric effect.

11.List out the characteristics of photons?(1)

The photons of light of frequency ν and wavelength λ will have energy, given by

Since photons are electrically neutral, they are unaffected by electric and magnetic fields.

📚12th Physics Most Repeated 5 Mark , 3 Marks & Compulsory Questions 2026

12.Define capacitance. Give its unit.(5)

The capacitance C of a capacitor is defined as the ratio of the magnitude of charge on either of the conductor plates to the potential difference existing between them.

The SI unit of capacitance is coulomb per volt or farad (F)

13.Define stopping potential(5)

Stopping potential is that value of the negative (retarding) potential given to the collecting electrode A which is just sufficient to stop the most energetic photoelectrons emitted and make the photocurrent zero

14.State Ampere’s circuital law.(4)

The line integral of magnetic field over a closed loop is μ0 times net current enclosed by the loop.

where I_enclosed is the net current linked by the closed loop C.

15.Define electric flux. Give its unit?(4)

The number of electric field lines crossing a given area kept normal to the electric field lines is called electric flux. It is usually denoted by the Greek letter Φ_E
its unit is Nm² C^–1.

Kirchoff’s Rule : (4)

16.State Kirchoff’s current Rule?

Kirchhoff’s current rule states that the algebraic sum of the currents at any junction of a circuit is zero. It is a statement of law of conservation of electric charge.

17.State Kirchoff’s voltage rule?

It states that in a closed circuit the algebraic sum of the products of the current and resistance of each part of the circuit is equal to the total emf included the circuit.

18.State Malus’s law?(4)

When a beam of plane polarised light of intensity I₀ is incident on an analyser, the intensity of light I transmitted from the analyser varies directly as the square of the cosine of the angle θ between the transmission axes of polariser and analyser This is known as Malus’ law.
I = I₀ cos²θ

19.State Fleming’s left hand rule.(4)

Stretch fore finger, the middle finger and the thumb of the left hand in mutually perpendicular directions. If,

Fore finger points the direction of magnetic field,
The middle finger points the direction of the electric current, then
Thumb will point the direction of the force experienced by the conductor.

Skip distance & Skip area?(4)

20.What is skip area?

The zone (in between A and B) where there is no reception of electromagnetic waves neither ground nor sky is known as skip zone or skip area

21.Define skip distance?

The shortest distance between the transmitter and the point of reception of the sky wave along the surface is called as the skip distance.

22.Mention the differences between interference and diffraction.(4)

	Interference	Diffraction
1	Equally spaced bright and dark fringes	Central bright is double the size of other fringes
2	Equal intensity for all bright fringes	Intensity falls rapidly for higher order fringes
3	Large number of fringes are obtained	Less number of fringes are obtained

23.What is Peltier effect?(3)

When an electric current is passed through a circuit of a thermocouple, heat is evolved at one junction and absorbed at the other junction. This is known as peltier effect.

24.Distinguish between Drift velocity and Mobility.(3)

25.State huygen’s principle?(3)

According to Huygens principle, each point on the wavefront behaves as the source of secondary wavelets spreading out in all directions with the speed of the wave. These are called as secondary wavelets. The envelope to all these wavelets gives the position and shape of the new wavefront at a later time

26.Write a note on electro-static shielding.(3)

The electric field inside the cavity of a conductor is zero. A sensitive electrical instrument which is to be protected from external electrical disturbance can be kept inside this cavity. This is called electrostatic shielding

27.State Joules law of heating(3)

It states that the heat developed in an electrical circuit due to the flow of current varies directly as

(i) the square of the current
(ii) the resistance of the circuit and
(iii) the time of flow.
H = I²RT

28.What is meant by Hysteresis ?(2)

The phenomenon of lagging of magnetic induction behind the magnetising field is called hysteresis.
Hysteresis means ‘lagging behind’

29.Define temperature co-efficient of resistance(2)

It is defined as the ratio of increase in resistivity per degree rise in temperature to its resistivity at T

30.What is distance of closest approach?(2)

The minimum distance between the centre of the nucleus and the alpha particle just before it gets reflected back through 180°is defined as the distance of closest approach r0 (also known as contact distance)

31.Why we do not see the wave properties of a baseball?(2)

The wave properties of a baseball are not visible because its large mass results in an extremely small de Broglie wavelength
λ =h/mv

32.What is myopia? What is its remedy?(2)

A person suffering from near sightedness (or) myopia cannot see distant objects clearly.
Remedy : It must be corrected using concave lens of focal length equal to the distance of the far point F from the eye.

33.What is Fresnel’s distance?(2)

Fresnel’s distance is the distance upto which the ray optics is obeyed and beyond which the ray optics is not obeyed; but, the wave optics becomes significant.

34.What is optical path? (2)

Optical path of a medium is defined as the distance d’ light travels in vacuum in the same time it travels a distance d in the medium.
d′ = nd

35.Define threshold frequency(2)

For a given metallic surface, the emission of photoelectrons takes place only if the frequency of incident light is greater than a certain minimum frequency called the threshold frequency.

36.Why steel is preferred in making Robots?(2)

For robots, aluminum and steel are the most common metals. steel is several times stronger. because of the inherent strength of metal, robot bodies are made using sheet, bar, rod, channel, and other shapes.

37.What is displacement current?(2)

The displacement current can be defined as the current which comes into play in the region in which the electric field (or the electric flux) is changing with time.

38.How will you increase the current sensitivity of a galvanometer?(2)

The current sensitivity of a galvanometer can be increased by

Increasing the number of turns, N
Increasing the magnetic induction, B
Increasing the area of the coil, A
Decreasing the couple per unit twist of the suspension wire, K.

39.What are Fraunhofer lines?(2)

When the spectrum obtained from the Sun is examined, it consists of large number of dark lines (line absorption spectrum). These dark lines in the solar spectrum are known as Fraunhofer lines

40.How will you define Q-factor?(2)

It is defined as the ratio of voltage across L or C at resonance to the applied voltage.

41.Define Curie?(2)

One curie was defined as number of decays per second in 1 g of radium and it is equal to 3.7×10¹⁰ . decays/s.
1 Curie =1 Ci = 3.7×10¹⁰ × decays/s. per second
1 Ci = 3.7×10¹⁰ Bq

42.Write the properties of cathode rays(2)

Cathode rays possess energy and momentum and travel in a straight line with high speed of the order of 10⁷ ms^-1.
It can be deflected by application of electric and magnetic fields.
The direction of deflection indicates that they contain negatively charged particles.

43.Define work function of a metal. Give its unit.(2)

The minimum energy needed for an electron to escape from the metal surface is called work function of that metal. The work function of the metal is denoted by φ0 and is measured in electron volt (eV).

44.Define: Resistivity or Electrical resistivity(2)

Electrical resistivity of a material is defined as the resistance offered to current flow by a conductor of unit length having unit area of cross section.

Its unit is ohm-metre Ωm

45.List out the properties of neutrino?(2)

It has zero charge;
It has an antiparticle called anti-neutrino.
Recent experiments showed that the neutrino has very tiny mass.
It interacts very weakly with the matter. Therefore, it is very difficult to detect.

46.What is Bremsstralung?(2)

When a fast moving electron penetrates and approaches a target nucleus, the interaction between the electron and the nucleus either accelerates or decelerates it which results in a change of path of the electron. The radiation produced from such decelerating electron is called Bremsstrahlung or braking radiation

47.State macroscopic form of Ohm’s Law || State ohms law?(2)

Macroscopic form of Ohm’s law can be stated as “the potential difference across a given conductor is directly proportional to the current passing throught it when the temperature remains constant”.
V = IR

48.During lightning, it is safer to sit inside a car than in an open ground or under tree Why?(2)

During lightning accompanied by a thunderstorm, it is always safer to sit inside a car or bus than in open ground or under a tree. The metal body of the car/bus provides electrostatic shielding, since the electric field inside is zero. During lightning, the charges flow through the body of the conductor to the ground with no effect on the person inside that bus.

49.What do you mean by doping?(2)

The process of adding impurities to the intrinsic semiconductor is called doping.

It increases the concentration of charge carriers in the semiconductor and in turn, its electrical conductivity. The impurity atoms are called dopants and its order is approximately 100 ppm (parts per million).

50.Draw the circuit diagram for CE configuration || Draw the circuit diagram of NPN transistor in common emitter configuration(2)

(a) Schematic circuit diagram (b) Circuit symbol

Addition 2 Marks : Appeared Once

1. Define Current density and give its unit.
Current density is defined as the current flowing per unit cross-sectional area of a conductor. $J=\frac{I}{A}$

Unit: A m⁻²

2. Why do clouds appear white?
Clouds appear white because water droplets scatter all wavelengths of sunlight equally, producing white light.

3. Give the definition of intensity of light according to quantum concept.
According to quantum theory, intensity of light is proportional to the number of photons incident per unit area per second.

4. Why capacitor blocks DC?
A capacitor blocks DC because after it gets fully charged, no current flows through it.

5. What are black holes?
Black holes are regions in space with extremely strong gravitational field from which even light cannot escape.

6. What is electric power and electric energy?
Electric Power: Rate at which electrical energy is consumed. $P = VI$

Electric Energy: Total electrical work done in a circuit. $E = Pt$

7. Define electric dipole moment. Give its unit.
Electric dipole moment is the product of magnitude of charge and the distance between the charges. $p = qd$

Unit: Coulomb-metre (C m)

Define Electric dipole. Give an example.
An electric dipole is a pair of equal and opposite charges separated by a small distance.
Example: Two charges +q and −q separated by distance.

8. Distinguish between polar molecule and non-polar molecule.

Polar molecule	Non-polar molecule
Has permanent dipole moment	No permanent dipole moment
Centres of charges do not coincide	Centres coincide
Example: H₂O	Example: CO₂

9. State Maxwell’s right hand cork screw rule.
If we rotate a right-handed screw using a screw driver, then the direction of current is same as the direction in which screw advances and the direction of rotation of the screw gives the direction of the magnetic field.

10. State Biot-Savart’s law.
The magnetic field due to a current element is directly proportional to the current and length of the element and inversely proportional to the square of the distance.

11. The electric field lines never intersect – Justify.
If field lines intersect, the electric field at that point would have two directions, which is impossible.

12. Write the two conditions for total internal reflection.

Light must travel from denser to rarer medium
Angle of incidence must be greater than the critical angle

13. What is Rayleigh’s criterion?
Two images are just resolved when the central maximum of one coincides with the first minimum of the other.

14. What is isobar? Give an example.
Atoms with same mass number but different atomic numbers.
Example: $^{40}_{18}Ar$ 1840Ar and $^{40}_{20}Ca$ 2040Ca

15. Calculate the radius of 79Au197 nucleus $R = R_0 A^{1/3}$ $R = 1.3 \times (197)^{1/3}$ $R \approx 7 \times 10^{-15} m$

16. Define ampere in terms of force.
One ampere is the current which, when flowing through two long parallel conductors of negligible cross-section placed 1 metre apart in vacuum, produces a force of 2 × 10⁻⁷ newton per metre length between them.

17. What is the principle of reversibility?
The path of a light ray remains the same when its direction is reversed.

18. State Coulomb’s law in electrostatics.
The electrostatic force between two charges is directly proportional to the product of their charges and inversely proportional to the square of the distance between them.

19. What is meant by electric field lines?
Electric field lines are imaginary lines representing the direction of electric field around a charge.

20. Define RMS value of an alternating current.
The RMS value of AC is the value of DC current that produces the same heating effect in a resistor.

21. Why does sky appear blue?
The sky appears blue due to Rayleigh scattering of sunlight by molecules in the atmosphere.

22. What is angle of polarisation?
The angle of incidence at which reflected light becomes completely plane polarised.

23. What is meant by excitation energy?
Excitation energy is the minimum energy required to raise an electron from ground state to a higher energy level.

24. Why electron is preferred over X-ray in microscope?
Electrons have much smaller wavelength, giving higher resolving power.

25. What are the properties of an equipotential surface?

Work done moving a charge along it is zero
Electric field is perpendicular to the surface
Two equipotential surfaces never intersect

26. What is magnetic permeability?
Magnetic permeability is the measure of the ability of a material to support magnetic field formation. $\mu = \frac{B}{H}$

27. Write down the postulates of Bohr atom model.

Electrons revolve in stable circular orbits
Angular momentum is quantized
Radiation emitted when electron jumps between energy levels

28. Define electrostatic potential. Give its unit.
Electrostatic potential is the work done in bringing a unit positive charge from infinity to a point.
Unit: Volt (V)

29. What are the constituent particles of neutron and proton?

Proton: 2 up quarks + 1 down quark
Neutron: 1 up quark + 2 down quark

30. Explain the concept of velocity selector.
A velocity selector is a device that selects charged particles with a particular velocity using perpendicular electric and magnetic fields. $v=\frac{E}{B}$

31. Derive the expression for de-Broglie wavelength of electrons. (Refer This question from book) $\lambda = \frac{h}{p}$

For electrons, $\lambda = \frac{h}{mv}$

32. Write short notes on X-ray.

X-rays are electromagnetic waves with very short wavelength
Produced when high speed electrons strike a metal target
Used in medical imaging and crystal analysis

33. State Lenz law.
The direction of induced current opposes the change in magnetic flux that produces it.

34. Give the properties of diamagnetic materials.

Weakly repelled by magnetic field
Susceptibility is negative
Example: Bismuth, Copper

35. What is isotope? Give an example.
Atoms having same atomic number but different mass numbers.
Example: $^{1}H, ^{2}H, ^{3}H$ 1H,2H,3H

36. What is isotone? Give an example.
Atoms having same number of neutrons but different atomic numbers.
Example: $^{14}C$ 14C and $^{15}N$ 15N

37. State Brewster’s law?

tani_p= n

Brewster’s law states that the tangent of the polarising angle for a transparent medium is equal to its refractive index. The polarising angle is known as Brewster’s angle which dependes on the nature of the refracting medium.

38. Is an ammeter connected in series or parallel in a circuit? Why?
An ammeter is connected in series because it must measure the same current flowing through the circuit.

39. Draw the input and output waveforms of a half wave rectifier.

Input: AC sine wave
Output: Only positive half cycles (pulsating DC)

40. Define power of a lens. Give its unit.
Power of a lens is the reciprocal of focal length (in metres). $P=\frac{1}{f}$

Unit: Dioptre (D)

41. What are the limitations of cyclotron?

Cannot accelerate neutral particles
Not suitable for very high-energy electrons due to relativistic effect

🧠 How to Use These Questions for Best Results

Revise these questions before each test or exam
Practice writing answers within time limits
Mark difficult questions for repeated revision
Combine this with textbook diagram practice
Focus on understanding concepts rather than memorizing

❓ Frequently Asked Questions

Are these questions enough for the public exam?

These questions cover frequently tested concepts based on past trends and yes you will be able to answer five to six questions from this set of questions.

From which papers are these questions selected?

They are compiled from government school examinations including midterms, quarterly, half-yearly, revision tests, and public exam papers from the last five years.

Do 2 mark questions repeat in Physics exams?

Yes. In many cases, exact questions from previous examinations are repeated in Tamil Nadu Physics exams. This collection is based on repeated patterns observed across recent government and public examination papers. However, students are still advised to understand the underlying concepts to handle possible variations in wording.

Is this page useful for last-minute revision?

Yes. This page is designed as a quick revision resource to help students recall important concepts efficiently before exams.

Keep visiting Padidaa.com for more exam-focused study materials and important question collections designed for Tamil Nadu Board students.