Home   »   Class 12 Physics Answer Key 2023

# CBSE Class 12 Physics Answer Key 2023, Questions Paper Solutions

## Class 12 Physics Answer Key 2023

CBSE Class 12 Physics Answer Key 2023: CBSE Physics Class 12 Exam 2023 has conducted on 06th March 2023 (Monday). No doubt every student after exiting the exam hall must be worried about how many marks he/she would be scoring, which question was wrong and how many questions could be expectedly correct. So instead of waiting for the result, they started searching for the questions asked in the exam. To minimise your fear and anxiety, here in this article, we have shared the complete Class 12 Physics Answer Key 2023 at a glance. No need to keep searching here and there just check all the questions with their correct answers.

## CBSE Class 12 Physics Answer Key 2023

As CBSE will not release the official Class 12 Physics Answer Key for Class 12 Physics Board Exam along with other subjects, we have provided the unofficial Physics Answer Key 2023 for Class 12 in this article.

 CBSE Class 12 Physics Answer Key 2023 Exam Conducting Body Central Board of Secondary Education Class CBSE Class 12 Exam Name Physics Post Category Answer Key Exam Date 06th March 2023 Class 12 Physics Answer Key (Unofficial ) 06th March 2023 Official Website https://www.cbse.nic.in/

## Class 12 Physics Answer Key 2023 & Solution

Here, we have provided the complete Class 12 Physics Answer Key 2023 with correct answers one by one. So if are looking for the complete CBSE Class 12 Physics Answer Key go through the solutions that are discussed by our faculty in their live session. Connect with them and know the correct answers to the questions asked in today’s exam.

## Class 12 Physics Answer Key & Solution 2023 (Set 1- 55/4/1)

The following questions were asked in Set 1- 55/4/1 and questions have been discussed by our faculty.

Q1. Two charges q1 and q2 are placed at the centres of two spherical conducting shells of radius r1 and r2 respectively. The shells are arranged such that their centres are d [ >(r1 + r2)] distance apart. The force on q2 due to q1 is:

Q2. An electron enters a uniform magnetic field with speed v. It describes a semicircular path and comes out of the field. The final speed of the electron is

a) zero
b) v
c) v/2
d) 2v

Q3. The magnetic field lines near a substance are as shown in the figure. The substance is:

a) Copper
b) Iron
c) Sodium
d) Aluminium

Q4. The figure shows the variation of current (I) with time (t) in four devices P, Q, R, and S. The device in which an alternating current flows is-

a) P
b) Q
c) R
d) S

Q5. The electromagnetic waves used in radar system are-

a) Infrared waves
b) Ultraviolet rays
c) Microwaves
d) X-rays

Q6. In Young’s double-slit experiment, the fringe width is ß. If the entire apparatus is immersed in a liquid of refractive index μ, new fringe width will be:

a) β
b) μβ
cμβ
dβ/μ2

Q7. Photons of energy 3.2 eV are incident on a photosensitive surface. If the stopping potential for the emitted electrons is 1.5 V, the work function for the surface is:

a) 1.5 eV
b) 1.7 eV
c) 3.2 eV
d) 4.7 eV

Q8. Which of the following statements is not true for nuclear forces?

a) They are stronger than Coulomb forces.
b) They have about the same magnitude for different pairs of nucleons.
c) They are always attractive.
d) They saturate as the separation between two nucleons increases

Q9. The direction of induced current in the loop abc is

a) along abc if I decrease
b) along acb if I increase
c) along abc if I is constant
d) along abc if I increase

Q10. An ac voltage v = vo sin wt is applied to a series combination of a resistor R and an element X. The instantaneous current in the circuit is I = Io sin (wt + Π /4). Then which of the following is correct?

a) X is a capacitor and Xc = √2
bX is an inductor and X1 = R
cX is an inductor and XL = √2 R
d) X is a capacitor and Xc =

Q11. A plane wavefront is incident on a concave mirror of radius of curvature R. The radius of the refracted wavefront will be:

a) 2R
b)
c) R/2
d) R/4

Q12. A proton and an alpha particle have the same kinetic energy. The ratio of de Broglie wavelengths associated with the proton to that with the alpha particle is

a) 1
b) 2
c) 2√2
d) 1/2

Q13. The potential energy of an electron in the second excited state in hydrogen atom is

a) -3.4 eV
b) -3.02 eV
c) -1.51 eV
d) -6.8 eV

Q14. The difference in mass of 7X nucleus and total mass of its constituent nucleons is 21.00 u. The binding energy per nucleon for this nucleus is equal to the energy equivalent of:

a) 3 u
b) 3.5 u
c) 7 u
d) 21 u

Q15. The threshold voltage for a p-n junction diode used in the circuit is 0.7 V. The type of biasing and current in the circuit are:

a) Forward biasing, 0 A
b) Reverse biasing, 0 A
c) Forward biasing, 5 mA
d) Reverse biasing, 2 mA

## Class 12 Physics Answer Key & Solution 2023 (Set 2)

Q1. An electric dipole of length 2 cm is placed at an angle of 30o with an electric field 2 x 105N/C. If the dipole experiences a torque of 8 x 10 -3 Nm, the magnitude of either charge of the dipole is

a) 4 µC
b) 7 µC
c) 8 mC
d) 2 mC

Q2. Two horizontal thin long parallel wires, separated by a distance r carry current I each in the opposite directions. The net magnetic field at a point midway between them will be

a) Zero
b) (µoI/2πr) vertically down
c) (2µoI/r) vertically upward
d) (µoI/πr) vertically down

Q3. Which of the following cannot modify an external magnetic field as shown in the figure?

a) Nickel
b) Silicon
c) Sodium
d) Copper

Q4. A square shaped coil of side 10cm, having 100 turns is placed perpendicular to a magnetic field which is increasing at 1T/s. The induced emf in the coil is

a) 0.1V
b) 0.5V
c) 0.75V
d) 1.0V

Q5. Which one of the following electromagnetic radiation has the least wavelength?

a) Gamma rays
b) Microwaves
c) Visible Light
d) X-rays

Q6. In Young’s double-slit experiment, the screen is moved away from the plane of the slits. What will be its effect on the following?
(i) Angluar separation of the fringes.
(ii) Fringe-width

a) Both (i) and (ii) remain constant
b) (i) remains constant, but (ii) decreases
c) (i) remains constant, but (ii) increases
d) Both (i) and (ii) increase

Q7. E, c and v represent the energy, velocity and frequency of a photon. Which of the following represents its wavelength?

a) hv/c2
b) hv
c) hc/E
d) hv/c

Q8. The ratio of the nuclear densities of two nuclei having mass numbers 64 and 125 is

a) 64/125
b) 4/5
c) 5/4
d) 1

Q9. The energy required by an electron to jump the forbidden band in silicon at room temperature  is about

a) 0.01 eV
b) 0.05 eV
c) 0.7 eV
d) 1.1 eV

Q10. The diagram shows four energy level of an electron in Bohr model of hydrogen atom. Identify the transition in which the emitted photon will have the highest energy.

a) I
b) II
c) III
d) IV

Q11. Which of the following graphs correctly represents the variation of a particle momentum with its associated de-Broglie wavelength?

Q12. The capacitors, each of 4µF are to be connected in such a way that the effective capacitance of the combination is 6µF. This can be achieved by connecting

a)  All three in parallel
b) All three in series
c) Two of them connected in series and the combination in parallel to the third.
d) Two of them connected in parallel and the combination in series to the third.

Q13. What is the ratio of inductive and capacitive reactance in an ac circuit?

a) ω2LC
b) LC2
c) LC/ω
d) ω2/L

Q14. In an interference experiment, third bright fringe is obtained at a point on the screen with a light of 700nm. What should be the wavelength of the light source in order to obtain the fifth bright fringe at the same point?

a) 420nm
b) 750nm
c) 630nm
d) 500nm

Q15. The radius of the nth orbit in Bohr model of hydrogen atom is proportional to

a) n2
b) 1/n2
c) n
d) 1/n

## Physics Class 12 Answer Key 2023 Pattern

This academic year 2022-23, CBSE had planned to take the exams annually. There will be 35 questions in all. The paper consists of a total of 5 sections for 35 questions. The duration of the exam is 3 hours. The marking scheme for Physics Class 12 Board Paper 2023 is as tabulated below-

 Physics Class 12 Pattern 2023 Sections No. of Questions Marks Type of Questions Section A 18 1 x 18 Multiple Choice Questions Section B 07 2 x 7 Very Short Answer Questions Section C 05 3 x 5 Short Answer Questions Section D 03 5 x 3 Long Answer Questions Section E 02 4 x 2 Case-Based Question Total 35 70 —

## Class 12 Physics Answer Key 2023- FAQs

### Q1. Where can I get Class 12 Physics Answer Key 2023?

Ans. Our teachers have discussed the Class 12 Physics Answer Key 2023 along with the questions paper solutions.

### Q2. How many questions are there in Class 12 Physics Exam 2023?

Ans. There were 35 questions for 70 marks divided into 5 sections asked in today's Class 12 Physics Exam.

## FAQs

### Q1. Where can I get Class 12 Physics Answer Key 2023?

Ans. Our teachers have discussed the Class 12 Physics Answer Key 2023 along with the questions paper solutions.

### Q2. How many questions are there in Class 12 Physics Exam 2023?

Ans. There were 35 questions for 70 marks divided into 5 sections asked in today's Class 12 Physics Exam.