12th Standard Physics Important Questions 2026 - 2027 Public Exam – 2 Mark, 3 Mark, 5 Mark Questions and Important Numerical Problems from Unit 1

 12th Standard Physics Important Questions – 2 Mark, 3 Mark, 5 Mark Questions and Important Numerical Problems from Unit 1

Kalvi Mini Physics 

Unit 1 is Electrostatics. I will tell you the important questions in Electrostatics. Study these questions very well for whatever exam you have — midterm exam, quarterly exam, half-yearly exam, revision exam, and main exam (public exam). Study for all these exams, because whatever questions they ask, the questions will come only from these important questions. I have also uploaded important questions and study material on my YouTube channel, so refer to that as well. I will tell you the important questions for all your examinations from Unit 1 – Electrostatics. So study these questions. If you have any doubt, you can email me, or you can comment on this post. Okay.

Now I will tell you the important questions. Please study these questions very well, because these are the most important and repeated questions in previous year examinations, and also these questions are based on important concepts in the textbook. Definitely these questions should come in your examination, so please prepare these questions for your exam.

Unit 1 – Electrostatics

Before telling you the important questions, first know this very well for all the units: please prepare the Multiple Choice Questions (book-back MCQs) very well. This is very important, because out of 70 marks, 15 marks are from MCQ questions, and out of those 15 marks (maximum 12 to 13 questions), most are from the book-back questions only. So prepare the book-back questions very well, okay.

Now, in Unit 1:

Short Answer Questions

Generally, they ask 2 mark and 3 mark questions from short answer questions.

Question No. 1 – What is meant by quantization of charge? (Very, very important)

Question No. 3 – What are the differences between Coulomb's force and gravitational force? (Very, very important — this is asked most often in the public examination as well. This is not only a 3 mark question; sometimes they ask this as a 5 mark question too. That is why this is very important.)

Question No. 4 – Write a short note on the superposition principle.

Question No. 5 – Define electric field.

Question No. 6 – What is meant by electric field lines?

Question No. 7 – Justify that electric field lines never intersect. (Very, very important — this question is asked most of the time in previous year examinations. I think you know the answer: if they intersect, they would create two directions simultaneously at that point, which is not possible. That is why they never intersect.)

Question No. 10 – Define electrostatic potential. (Very important)

Question No. 11 – What is an equipotential surface? (Very, very important)

Question No. 13 – Give the relation between electric field and electric potential.

Question No. 14 – Define electrostatic potential energy.

Question No. 15 – Define electric flux.

Question No. 19 – What is dielectric strength?

Question No. 20 – Define capacitance and give its unit.

Question No. 21 – What is corona discharge?

These are the most important 2 mark and 3 mark questions from Unit 1.

Important 5 Mark Questions (Long Answer Questions – Roman Numeral III)

Question No. 1 – Basic properties of electric charge. (This question is also asked most of the time as a 3 mark question.)

Question No. 3 – Define electric field and discuss its various aspects. (Most important 3 mark question.)

Question No. 4 – Calculate the electric field due to a dipole on its axial line and equatorial plane. (Very, very important 5 mark question, because this question is repeatedly asked in previous year quarterly examinations, half-yearly examinations, and public exams as well. This is a single question, but in the exam they ask either the axial line or the equatorial plane, so study both.)

Question No. 6 – Derive an expression for electrostatic potential due to a point charge. (Very, very important)

Question No. 7 – Derive an expression for electrostatic potential due to an electric dipole. (Very, very important)

Question No. 11 – Derive an expression for electric field due to an infinitely long charged wire. (Very, very important)

Question No. 17 – Derive an expression for capacitance of a parallel plate capacitor. (Very, very important)

Question No. 20 – Derive an expression for resultant capacitance when capacitors are connected in series and in parallel. (Very, very important)

Question No. 22 – Explain in detail the construction and working of the Van de Graaff generator. (Very, very important)

These are all the very important 2 mark, 3 mark, and 5 mark questions from Unit 1. Study these questions very well for all your examinations.

Important Numerical Problems

From the book-back exercise questions, Question Numbers 1, 2, 4, and 15 are important numerical problems. Also, the worked examples inside the book chapter are very important, because they are compulsorily asked as well.

Important Topics to Remember

In Electrostatics, the important topics to study are:

• Point charge
• Coulomb's law
• Dipole

Under Coulomb's law, the important topics are electric field and electric potential. Under electric field, the important topics are electric flux, Gauss's law, and the Van de Graaff generator. Study all these concepts very well, along with all the types of questions and uses related to them.

In this unit, especially focus on: axial line and equatorial plane, point charge, and electric dipole — these are the most important concepts.