JAC Class 12 Physics Question Paper 2019 with Solution

About this paper

This is the Jharkhand Academic Council (JAC) Class 12 Physics paper from the 2019 board examination, with an answer under each question. The printed scheme is 70 marks: Group A is 15 objective questions of one mark, Group B eight questions of two marks, Group C eight of three marks and Group D three of five marks. Short questions include quantisation of charge, torque on a dipole, eddy currents and the symbols of the OR and AND gates. A three-mark item places a 4.5 cm needle 12 cm from a convex mirror of focal length 15 cm, and another gives light of frequency 7.21×10¹⁴ Hz ejecting electrons at 6.0×10⁵ m/s. Each five-mark question has an alternative. Time is not printed.

Exam

JAC Class 12

Subject

Physics

Year

2019

Maximum marks

70

Questions

20

Pages

8

Answers included

Yes

Paper pattern

• Group A

  15 marks

  15 objective questions, one mark each

• Group B

  16 marks

  Questions 2–9, two marks each

• Group C

  24 marks

  Questions 10–17, three marks each

• Group D

  15 marks

  Questions 18–20, five marks each, each with an alternative

Topics covered

• Electrostatics and capacitors
• Current electricity and internal resistance
• Magnetism and paramagnetic substances
• Eddy currents and electromagnetic induction
• Force on a current-carrying conductor
• Alternating current, reactance and impedance
• Electromagnetic waves and wave propagation
• Ray optics, mirrors and prisms
• Polarisation and Brewster's law
• Photoelectric effect
• Nuclei, isotopes, isobars and isotones
• Semiconductors, Zener diodes and logic gates

Questions from this paper

1. State the principle of conservation of electric charge and the principle of quantisation of charge.
2. What are eddy currents? Mention two applications.
3. A 4.5 cm needle is placed 12 cm away from a convex mirror of focal length 15 cm. Give the location of the image and the magnification.
4. Light of frequency 7.21×10¹⁴ Hz is incident on a metal surface. Electrons with a maximum speed of 6.0×10⁵ m/s are ejected. What is the threshold frequency for photoemission?
5. What are isotopes, isobars and isotones? Give one example of each.
6. What is the angle of minimum deviation? For refraction through a prism, establish the relation between refractive index, the angle of the prism and the angle of minimum deviation.