Class 12 Physics Sample Question Paper Set 5
Time: 3 Hours
Maximum Marks: 70
General Instructions:
- All questions are compulsory.
- The question paper consists of four sections – A, B, C, and D.
- Section A contains 15 multiple choice questions of 1 mark each.
- Section B contains 7 questions of 2 marks each.
- Section C contains 7 questions of 3 marks each.
- Section D contains 3 questions of 5 marks each.
- There is no overall choice in the paper, but internal choices are provided in questions.
- Use of calculators is not permitted.
- Draw neat diagrams wherever necessary.
Section A: Multiple Choice Questions (1 Mark each)
- The electric field inside a conductor is:
- a) Zero
- b) Constant
- c) Infinite
- d) Variable
- According to Coulomb’s law, the force between two charges is:
- a) Directly proportional to the product of the charges
- b) Inversely proportional to the product of the charges
- c) Directly proportional to the square of the distance between them
- d) Inversely proportional to the square of the distance between them
- Kirchhoff’s current law is based on:
- a) Conservation of energy
- b) Conservation of charge
- c) Conservation of momentum
- d) Conservation of mass
- Which of the following is the correct formula for drift velocity?
- a) vd = I/nqA
- b) vd = A/nIq
- c) vd = q/nIA
- d) None of the above
- The SI unit of magnetic permeability is:
- a) Weber
- b) Tesla
- c) Henry/meter
- d) Joule
- The phenomenon of electromagnetic induction was discovered by:
- a) Maxwell
- b) Faraday
- c) Ampere
- d) Oersted
- A current-carrying conductor in a magnetic field experiences:
- a) Lorentz force
- b) Gravitational force
- c) Electric force
- d) None of the above
- The magnetic flux through a closed surface is:
- a) Always zero
- b) Infinite
- c) Proportional to the charge enclosed
- d) Proportional to the current
- A transformer works on the principle of:
- a) Electromagnetic induction
- b) Mutual inductance
- c) Static induction
- d) Electrostatics
- The speed of electromagnetic waves in a vacuum is:
- a) 3 × 108 m/s
- b) 2 × 108 m/s
- c) 1.5 × 108 m/s
- d) None of the above
- Which of the following is not a property of electromagnetic waves?
- a) They can travel through a vacuum
- b) They transfer energy
- c) They have electric and magnetic components
- d) They require a medium for propagation
- Lenz's law helps determine the:
- a) Magnitude of induced EMF
- b) Direction of induced current
- c) Strength of the magnetic field
- d) None of the above
- In an AC circuit, the phase difference between voltage and current in a pure inductor is:
- a) 0°
- b) 90°
- c) 180°
- d) None of the above
- The refractive index of a medium depends on:
- a) Wavelength of light
- b) Speed of light in vacuum
- c) Temperature
- d) All of the above
- Which of the following is correct about electromagnetic waves?
- a) They require a medium to propagate
- b) They travel at different speeds in different media
- c) They consist of oscillating electric and magnetic fields
- d) Both b) and c)
Section B: Short Answer Questions (2 Marks each)
- State Gauss's law and explain its significance. Or What are electric dipoles? Explain the behavior of an electric dipole in a uniform electric field.
- Explain Ohm’s law in terms of electron flow in a conductor.
- Derive the expression for the power dissipated in an electrical circuit.
- Discuss the working principle of a cyclotron. Or State Ampere’s Circuital Law and explain its application.
- Explain Lenz’s law in electromagnetic induction with an example.
- What are electromagnetic waves? Describe their properties. Or Explain the displacement current and its importance in Maxwell’s equations.
- What is mutual inductance? Derive the expression for it in terms of Faraday’s law.
Section C: Long Answer Questions (3 Marks each)
- Derive the expression for the electric field due to a uniformly charged infinite plane sheet. Or Describe the concept of potential difference and capacitance in a parallel plate capacitor.
- Explain the working of a moving coil galvanometer. Discuss its sensitivity.
- Discuss the energy stored in an inductor and derive the formula for it. Or What is the principle of superposition in magnetism?
- What is the relationship between current density, electric field, and resistivity?
- Explain the concept of resonance in an LCR circuit. Or What is a transformer? Explain the principle of a step-up transformer.
- What is electromagnetic induction? Explain its significance in modern-day technology.
- Describe the electromagnetic spectrum and its uses in communication.
Section D: Long Answer Questions (5 Marks each)
- Derive the expression for the electric potential due to a dipole at any point on its axial line. Or Discuss the capacitor's behavior in a series and parallel combination. Derive the relevant formulas.
- Derive the expression for the magnetic field inside a solenoid carrying current. Or Explain the working of a cyclotron with the help of a diagram and relevant equations.
- Explain the working of an AC generator. Derive the expression for the induced EMF. Or What is the principle of a transformer? Derive the relation between the primary and secondary voltage.
Section E: Comprehension-Based Question (5 Marks)
Read the passage below carefully and answer the following questions:
Faraday’s law of electromagnetic induction states that a change in magnetic flux induces an electromotive force (EMF) in a conductor. This principle forms the basis of many electrical devices, such as transformers and electric generators. Lenz's law provides the direction of the induced EMF, which opposes the change in flux. The magnitude of the induced EMF is directly proportional to the rate of change of the magnetic flux.
- Explain Faraday’s law of electromagnetic induction with an example.
- What is Lenz’s law, and how does it complement Faraday’s law?
- Describe an application of electromagnetic induction in everyday life.
- How does the rate of change of magnetic flux affect the induced EMF in a conductor?
- What happens when the direction of magnetic flux changes rapidly?
