CBSE Class 12 Physics Term-1 Question Paper 2021 with Solution

About this paper

This is the CBSE Class 12 Physics (Theory) Term-I question paper from the 2021–22 session, Series SSJ/1, Set 4, code 055/1/4. It is an OMR-based paper of 55 multiple-choice questions for 35 marks in 90 minutes, with 20 minutes of extra reading time. All questions carry equal marks and 45 are to be attempted: any 20 of the 25 in Section A, any 20 of the 24 in Section B and any 5 of the 6 in Section C. There is no negative marking. Section B includes five assertion–reason questions, and Section C ends with a four-question case study on two cells joined in a battery. The questions cover electrostatics, current electricity, magnetism, electromagnetic induction and alternating current. This copy has the questions only, without solutions.

Exam

CBSE Class 12

Subject

Physics

Year

2021

Paper code

055/1/4

Maximum marks

35

Time allowed

90 minutes + 20 min reading

Questions

55

Pages

12

Answers included

No, questions only

Paper pattern

• Section A

  Questions 1–25, multiple-choice; attempt any 20

• Section B

  Questions 26–49, multiple-choice including five assertion–reason questions (45–49); attempt any 20

• Section C

  Questions 50–55, multiple-choice including a four-question case study on combining cells; attempt any 5

Topics covered

• Electric charges and fields
• Electrostatic potential and capacitance
• Current electricity
• Moving charges and magnetism
• Magnetism and matter
• Electromagnetic induction
• Alternating current

Questions from this paper

1. A pure inductor of 318 mH and a pure resistor of 75 Ω are connected in series to a 50 Hz ac source. The voltage across the 75 Ω resistor is found to be 150 V. What is the source voltage?
2. In a potentiometer experiment, the balancing length with a cell is 120 cm. When the cell is shunted by a 1 Ω resistance, the balancing length becomes 40 cm. Find the internal resistance of the cell.
3. An electric dipole of dipole moment 4 × 10⁻⁵ C m, kept in a uniform electric field of 10⁻³ N C⁻¹, experiences a torque of 2 × 10⁻⁸ N m. Find the angle which the dipole makes with the electric field.
4. The magnetic flux linked with a coil is given by φ = 5t² + 3t + 16, where φ is in webers and t in seconds. What is the induced emf in the coil at t = 5 s?
5. Assertion: A transformer is used to increase or decrease ac voltage only. Reason: A transformer works on the basis of mutual induction.
6. Two charged spheres A and B with radii in the ratio 1 : 2 are connected together with a conducting wire. What is the ratio of their surface charge densities?