# 12th Physics Important Questions 2022

## 12th Physics Important Questions Reduced Syllabus 2022

12th Physics Public Exam Important Questions Volume 1 and Volume 2 based on reduced syllabus 2022 Tamil Medium and English Medium Download PDF. 12th Physics Public Exam Model Questions. 12th Physics Free Online Test.

## Volume 1

### 12th Physics Important 2 Marks

- Define ‘Electric dipole and dipole moment?
- Define ‘electrostatic potential”.
- Define ‘electric flux’. Mention its unit.
- Define ‘capacitance’. Give its unit.
- What is corona discharge?
- State Coulomb’s law
- Distinguish between drift velocity and mobility.
- Define electrical resistivity. Mention its unit.
- Define temperature coefficient of resistance. Mention its unit.
- Distinguish electric power and electric energy?
- What is the Thomson effect?
- What is the Peltier effect?
- Define magnetic flux. Mention its unit.
- State Coulomb’s inverse law in magnetism.
- State Ampere’s circuital law.
- State Flemmings left-hand rule
- How is a galvanometer converted into i)ammeter ii) voltmeter
- State Fleming’s right-hand rule.
- Mention the ways of producing induced emf.
- Define electric resonance.
- How will you define Q-factor?
- Write down the integral form of modified Ampere’s circuital law.
- What is meant by Fraunhofer lines?
- Why are em waves non-mechanical?

### 12th Physics Important 3 Marks

- Derive an expression for the torque experienced by a dipole due to a uniform electric field.
- Derive an expression for electrostatic potential due to a point charge.
- Obtain the expression for capacitance for a parallel plate capacitor.
- Obtain the expression for energy stored in the parallel plate capacitor.
- Obtain the macroscopic form of Ohm’s law from its microscopic form and discuss its limitation.
- State and explain Kirchhoff’s rules.
- Explain the equivalent resistance of a series and parallel resistor network
- Explain the determination of the internal resistance of a cell using a voltmeter.
- Find the magnetic induction due to a long straight conductor using Ampere’s circuital law.
- Give an account of magnetic Lorentz force.
- Explain how a galvanometer is converted into an ammeter.
- Explain how a galvanometer is converted into a voltmeter.
- How will you induce an emf by changing the area enclosed by the coil?
- Mention the various energy losses in a transformer.
- Find out the phase relationship between voltage and current in a pure resistive circuit.
- Assuming that the length of the solenoid is large when compared to its diameter, find the equation for its inductance
- What are emission spectra? Give their types.
- What are absorption spectra? Give their types.
- Write down the properties of electromagnetic waves

### 12th Physics Important 5 Marks

- Calculate the electric field due to a dipole on its axial line.
- Derive an expression for electrostatic potential due to an electric dipole.
- Obtain the expression for electric field due to an infinitely long charged wire.
- Derive the expression for resultant capacitance, when capacitors are connected in series and in parallel.
- Explain in detail the construction and working of a Van de Graaff generator.
- Describe the microscopic model of current and obtain the general form of Ohm’s law.
- Obtain the condition for bridge balance in Wheatstone’s bridge
- Deduce the relation for the magnetic induction at a point due to an infinitely long straight conductor carrying current.
- Obtain an expression for the force between two long parallel current-carrying conductors.
- Obtain an expression for the force on a current-carrying conductor placed in a magnetic field.
- Show mathematically that the rotation of a coil in a magnetic field over one rotation induces an alternating emf of one cycle.
- Explain the construction and working of the transformer.
- Find out the phase relationship between voltage and current in a pure inductive circuit.
- Derive an expression for the phase angle between the applied voltage and current in a series RLC circuit.

## Volume 2

### 12th Physics Important 2 Marks

- State the laws of refraction (OR) Snells law.
- What is critical angle and total internal reflection?
- What is Rayleigh’s scattering?
- Why does the sky appear blue?
- What is the reason for the reddish appearance of the sky during sunset and sunrise?
- Why do clouds appear white?
- What is Huygens’ principle?
- What is the bandwidth of the interference pattern?
- What is plane polarised, unpolarized and partially polarised light?
- State Brewster’s law
- Define the work function of a metal. Give its unit.
- What is the photoelectric effect?
- How will you define threshold frequency?
- Define stopping potential.
- What is meant by excitation energy.
- Define the ionization energy and ionization potential.
- Define impact parameter.
- What is mass defect?
- What is binding energy of a nucleus? Give its expression.
- Calculate the energy equivalent of 1 atomic mass unit.
- What is mean life of nucleus? Give the expression.
- What is meant by activity or decay rate? Give its unit.
- Define curie.
- What do you mean by doping?
- Distinguish between intrinsic and extrinsic semiconductors.
- What is rectification?
- What is an integrated circuit?
- What is modulation?
- Define center frequency or resting frequency in frequency modulation.

### 12th Physics Important 3 Marks

- Derive the relation between f and R for a spherical mirror.
- What is an optical path? Obtain the equation for the optical path of a medium of thickness d and refractive index n.
- Obtain the equation for apparent depth.
- Obtain the equation for the critical angle
- Mention the differences between interference and diffraction
- State and obtain Malus’ law
- List the uses of polaroids.
- What is the angle of polarisation and obtain the equation for angle of polarisation?
- State and obtain Brewster’s law.
- List out the laws of the photoelectric effect.
- Give the construction and working of photoemissive cell.
- Derive an expression for de Broglie wavelength of electrons.
- Write the applications fo photocells.
- Write the properties of cathode rays.
- Write down the postulates of Bohr atom model.
- Derive the energy expression for hydrogen atoms using the Bohr atom model.
- What are the properties of nuclear force?
- Discuss the alpha decay process for example.
- Discuss the gamma decay process for an example.
- Discuss the properties of neutrino and its role in beta decay
- Transistor functions as a switch. Explain.
- State and prove De Morgan’s First and Second theorems.
- What are the advantages and limitations of FM?

### 12th Physics Important 5 Marks

- Derive the mirror equation and the equation for lateral magnification.
- Describe Fizeau’s method to determine the speed of light.
- Obtain the lens maker’s formula and mention its significance.
- Derive the equation for the angle of deviation produced by a prism and thus obtain the equation for the refractive index of the material of the prism
- What is dispersion? Obtain the equation for the dispersive power of a medium.
- Obtain the equation for bandwidth in Young’s double-slit experiment.
- Discuss a simple microscope and obtain the equations for magnification for near point focusing and normal focusing.
- Obtain Einstein’s photoelectric equation with the necessary explanation.
- Describe briefly Davisson – the Germer experiment which demonstrated the wave nature of electrons
- Explain the J.J. Thomson experiment to determine the specific charge of electrons.
- Discuss the spectral series of the hydrogen atoms.
- Obtain the law of radioactivity.
- Obtain an expression for the radius and velocity of the electron in the nth orbit.
- Draw the circuit diagram of a half-wave rectifier and explain its working.
- Explain the construction and working of a full-wave rectifier.