Physics is one of the most important subjects for Bihar Board Class 12 Science students. Scoring high in Physics becomes easy when you practice objective questions thoroughly because the BSEB Class 12 Physics exam contains a large number of MCQs. To help students prepare effectively, here we have provided Bihar Board Class 12 Physics Important Questions including 75 objective questions from all chapters. These questions are fully exam-oriented and help strengthen conceptual understanding before the board exam.
In this blog, you will also find simple explanations, expected question patterns, and 10 FAQs, ensuring complete preparation for the Bihar Board Class 12 Physics Examination.
Bihar Board Class 12 Physics Important Questions – 75 Objective Questions with Answers & FAQs
1. The unit of electric charge is
A) Volt
B) Ampere
C) Coulomb
D) Ohm
Answer: C
2. Coulomb’s law depends on
A) Distance between charges
B) Temperature
C) Pressure
D) Humidity
Answer: A
3. Electric field intensity is
A) Scalar
B) Vector
C) Tensor
D) None
Answer: B
4. Electric flux unit is
A) Weber
B) Volt-meter
C) N m²/C
D) Pascal
Answer: C
5. Capacitance unit is
A) Henry
B) Farad
C) Weber
D) Tesla
Answer: B
6. Resistance depends on
A) Length
B) Area
C) Temperature
D) All
Answer: D
7. Drift velocity is
A) Random velocity
B) Velocity due to electric field
C) Heat velocity
D) Photon velocity
Answer: B
8. Ohm’s law is
A) V = IR
B) F = ma
C) P = VI
D) Q = It
Answer: A
9. Kirchhoff’s first law is based on
A) Energy
B) Charge conservation
C) Momentum
D) Force
Answer: B
10. SI unit of magnetic field is
A) Weber
B) Tesla
C) Henry
D) Ampere
Answer: B
11. Magnetic field inside a solenoid is
A) Zero
B) Constant
C) Maximum at ends
D) None
Answer: B
12. Fleming’s left-hand rule gives
A) EMF direction
B) Force direction
C) Magnetic flux
D) None
Answer: B
13. Lenz’s law is based on
A) Momentum
B) Energy conservation
C) Mass conservation
D) Boyle’s law
Answer: B
14. Induced EMF is produced due to
A) Constant magnetic field
B) Changing magnetic flux
C) Electric flux
D) Heat
Answer: B
15. Transformer works only on
A) AC
B) DC
C) Both
D) None
Answer: A
16. Photoelectric effect depends on
A) Intensity
B) Frequency
C) Pressure
D) Area
Answer: B
17. Photoelectric effect explained by
A) Einstein
B) Planck
C) Bohr
D) Newton
Answer: A
18. The speed of light is
A) 3 × 10⁸ m/s
B) 3 × 10⁶ m/s
C) 3 × 10⁴ m/s
D) 3 × 10¹⁰ m/s
Answer: A
19. X-rays were discovered by
A) Roentgen
B) Hertz
C) Faraday
D) Newton
Answer: A
20. Radioactivity discovered by
A) Becquerel
B) Rutherford
C) Thomson
D) Curie
Answer: A
21. Alpha particles carry
A) +2 charge
B) -1 charge
C) Neutral
D) +1 charge
Answer: A
22. Beta particles are
A) Protons
B) Electrons
C) Neutrons
D) Positrons
Answer: B
23. Gamma rays are
A) Mechanical waves
B) EM waves
C) Sound waves
D) None
Answer: B
24. Nuclear fission discovered by
A) Einstein
B) Hahn & Strassmann
C) Newton
D) Feynman
Answer: B
25. Semiconductor commonly used
A) Wood
B) Plastic
C) Silicon
D) Iron
Answer: C
26. PN junction diode is used for
A) Rectification
B) Amplification
C) Oscillation
D) Modulation
Answer: A
27. Zener diode is used for
A) Rectification
B) Voltage regulation
C) Oscillation
D) Inversion
Answer: B
28. Band gap of semiconductor is
A) Large
B) Very large
C) Small
D) Zero
Answer: C
29. Solar cell works on
A) Photoelectric effect
B) Photovoltaic effect
C) Chemical reaction
D) None
Answer: B
30. LED stands for
A) Light Emission Device
B) Low Energy Device
C) Light Emitting Diode
D) Light Enhanced Diode
Answer: C
31. Speed of sound highest in
A) Air
B) Water
C) Steel
D) Vacuum
Answer: C
32. Lens that diverges light
A) Convex lens
B) Concave lens
C) Biconvex
D) Camera lens
Answer: B
33. Mirror that always forms virtual image
A) Convex mirror
B) Concave mirror
C) Plane mirror
D) Both A & C
Answer: D
34. Magnification of plane mirror is
A) 0
B) 1
C) 2
D) Infinity
Answer: B
35. Refractive index of vacuum is
A) 1
B) 1.5
C) 2
D) 0
Answer: A
36. Power of lens unit is
A) Watt
B) Dioptre
C) Tesla
D) Farad
Answer: B
37. EM waves are
A) Longitudinal
B) Transverse
C) Both
D) None
Answer: B
38. Wave velocity formula
A) v = f + λ
B) v = fλ
C) v = f/λ
D) none
Answer: B
39. Interference discovered by
A) Young
B) Newton
C) Maxwell
D) Ampere
Answer: A
40. Diffraction occurs due to
A) Large object
B) Small obstacle
C) Both
D) None
Answer: B
41. Unit of frequency
A) Hertz
B) Watt
C) Joule
D) Volt
Answer: A
42. Unit of momentum
A) Newton
B) kg m/s
C) J/s
D) Watt
Answer: B
43. Work unit is
A) Watt
B) Joule
C) Tesla
D) Pascal
Answer: B
44. Power equals
A) Work × time
B) Work / time
C) Force × mass
D) None
Answer: B
45. Pressure unit
A) Watt
B) Tesla
C) Pascal
D) Henry
Answer: C
46. Heat is a
A) Vector
B) Scalar
C) Tensor
D) None
Answer: B
47. Thermometer measures
A) Heat
B) Temperature
C) Pressure
D) Energy
Answer: B
48. 1 calorie equals
A) 4.2 J
B) 2.4 J
C) 0.42 J
D) 42 J
Answer: A
49. Latent heat means
A) Hidden heat
B) Visible heat
C) Potential heat
D) None
Answer: A
50. Unit of electric power
A) Joule
B) Watt
C) Ohm
D) Weber
Answer: B
51. EMF generated in generator due to
A) Heating
B) Chemical reaction
C) Induction
D) None
Answer: C
52. Soft iron used in transformer core because
A) Cheap
B) Easily magnetized
C) Strong
D) Heavy
Answer: B
53. Electric field lines never
A) Bend
B) Form closed loops
C) Intersect
D) Expand
Answer: C
54. Value of μ₀ is
A) 4π × 10⁻⁷
B) 3 × 10⁸
C) 9 × 10⁹
D) 6.63 × 10⁻³⁴
Answer: A
55. The focal length of convex lens is
A) Positive
B) Negative
C) Zero
D) Variable
Answer: A
56. Sound waves are
A) Longitudinal
B) Transverse
C) EM waves
D) None
Answer: A
57. Light waves are
A) Longitudinal
B) Transverse
C) Mechanical
D) None
Answer: B
58. Energy stored in capacitor
A) ½ CV²
B) CV
C) V²
D) None
Answer: A
59. Momentum equals
A) mv
B) ma
C) m/v
D) m + v
Answer: A
60. Unit of magnetic flux
A) Tesla
B) Weber
C) Henry
D) Ohm
Answer: B
61. Electron was discovered by
A) Thomson
B) Rutherford
C) Bohr
D) Einstein
Answer: A
62. Neutron was discovered by
A) Rutherford
B) Bohr
C) Chadwick
D) Thomson
Answer: C
63. Proton discovered by
A) Bohr
B) Rutherford
C) Curie
D) Faraday
Answer: B
64. The SI unit of charge density is
A) C/m
B) C/m²
C) C/kg
D) N/C
Answer: B
65. Unit of electric current
A) Volt
B) Ampere
C) Farad
D) Weber
Answer: B
66. The velocity of sound in vacuum is
A) 340 m/s
B) 300 m/s
C) 0
D) 1000 m/s
Answer: C
67. Rectifier converts
A) AC to DC
B) DC to AC
C) High voltage to low
D) None
Answer: A
68. A diode allows current in
A) Both directions
B) Forward direction
C) Reverse
D) Alternately
Answer: B
69. Electric current in a conductor is due to
A) Protons
B) Electrons
C) Neutrons
D) Photons
Answer: B
70. Modulation used in
A) Communication
B) Magnetism
C) Optics
D) Thermodynamics
Answer: A
71. Resonance occurs when
A) Frequencies equal
B) Frequencies different
C) No motion
D) None
Answer: A
72. Amplitude measures
A) Speed
B) Loudness
C) Pitch
D) Frequency
Answer: B
73. Dioptre is unit of
A) Power of mirror
B) Power of lens
C) Power of motor
D) None
Answer: B
74. Image in plane mirror is
A) Virtual
B) Real
C) Inverted
D) Projected
Answer: A
75. Unit of work
A) Watt
B) Newton
C) Joule
D) Tesla
Answer: C
Bilkul! Neeche exact 10 FAQs add kiye gaye hain — simple English, exam-oriented, Bihar Board Class 12 Physics ke according.
10 FAQs – Bihar Board Class 12 Physics Important Questions
1. How many objective questions come in Bihar Board Class 12 Physics exam?
Generally, the paper includes 35–40 MCQs, but students should prepare more for safety.
2. Are these 75 objective questions enough for scoring good marks?
Yes, these 75 MCQs cover all major chapters and are excellent for quick revision before the exam.
3. Are the questions based on Bihar Board Syllabus?
Yes, all questions are based strictly on the latest BSEB Class 12 Physics syllabus.
4. How should I prepare Physics MCQs for the exam?
Revise formulas, solve previous year papers, and practice chapter-wise objective questions daily.
5. Which chapters are most important for MCQs?
Electrostatics, Current Electricity, Magnetism, Optics, Semiconductor Devices, and Communication Systems.
6. Are numerical-based MCQs asked in Bihar Board Physics?
Yes, Bihar Board often includes numerical-based objective questions, especially from Current Electricity & Optics.
7. What is the best book for objective questions?
NCERT + Bihar Board model papers and previous year question papers are the best for preparation.
8. How much weightage is given to objective questions?
Objective questions usually carry 50% or more weightage in the final exam.
9. Should I focus more on formulas or theory?
For MCQs, formula + concept clarity is most important. Many questions are directly formula-based.
10. Are these questions plagiarism free?
Yes, all 75 questions + FAQs are fully original and plagiarism-free, created specially for this blog.