CBSE Class 12 Physics Answer Key 2024, Question Paper PDF All Sets 1,2,3

CBSE Class 12 Physics Answer Key 2024: The Class 12 Physics Board Exam 2024 has been conducted today i.e., March 04, 2024 by the Central Board of Secondary Education at various examination centers. The exam has been started from 10:30 am till 01:30 pm. As the exam is successfully conducted, students can check and download the complete CBSE Class 12 Physics Answer Key 2024 with Question papers analysis. The direct link to download the CBSE Class 12 Physics Answer Key 2024 with Question Paper PDF has been updated here.

CBSE Class 12 Physics Answer Key 2024

The CBSE Board Class 12 Physics board exam 2024 has been conducted today i.e., March 04, 2024 in offline mode i.e., pen and paper mode. Students are allotted a time duration of 3 hours to complete the Physics exam whereas an extra 15 minutes will be given for reading the question paper. Physics among all science subjects is considered physics as a difficult subject, but if the students get familiar with the fundamental concepts, it becomes easy for them to pass the board exams with overall good marks. After the successful conduction of the CBSE Class 12 Physics Exam 2024 students can check the complete Class 12 Physics answer key 2024 here.

Class 12 Physics Answer Key 2024

The CBSE Class 12th Physics examination 2024 comprises a total of 100 marks out of which 70 marks will be for the Class 12th Physics theory exam while the rest 30 marks will be for the Physics Practical exam and viva. There will be a total of 33 problems in the CBSE Class 12th Physics Question Paper. All these questions will be divided into 5 different sections that are: Section A, Section B, Section C, Section D, and Section E.

CBSE Class 12 Physics Answer Key 2024
Exam Conducting Body	Central Board of Secondary Education
Name of the Examination	CBSE Class 12th Physics Examination 2024
Category	Answer Key
Status	Released
CBSE Class 12th Physics Exam Date 2024	March 04, 2024
Class 12th Physics Theory exam Total Marks	70 Marks
Negative Marking	No negative marking
Mode of answer key availability	Online mode
Official Website	https://www.cbse.nic.in/

Class 12 Physics Answer Key 2024 All Set

Class 12 Physics Answer Key 2024 Paper Code: 55/4/1

1. Two charges + q each are kept ‘2a’ distance apart. A third charge – 2q is placed midway between them. The potential energy of the system is-
Answer: (C) -7q2 /8πε0a

2. Two identical small conducting balls and B2 are given -7 pC and + 4 B1 PC charges respectively. They are brought in contact with a third identical ball B3 and then separated. If the final charge on each ball is -2 pC, the initial charge on B3 was
Answer:(B) – 3pC

3. The quantum nature of light explains the observations on the photoelectric effect as-
Answer: (B) the maximum kinetic energy of photoelectrons depends only on the frequency of incident radiation.

4. The radius (rn) of nth orbit in Bohr model of hydrogen atom varies with n
Answer: (C) rn & n²

5. A straight wire is kept horizontally along east-west direction. If a steady current flows in wire from east to west, the magnetic field at a point above the wire will point towards
Answer: (C) North

6. The magnetic susceptibility for a dismagnetic material is
Answer:  (A) small and negative

7. A galvanometer of resistance 100 2 is converted into an ammeter of range (0-1 A) using a resistance of 0.1 Q. The ammeter will show full scale deflection for a current of about
Answer: (D) 0.1 A

8. A circular loop A of radius R carries a current L. Another circular loop B of radius r (= R/20) placed concentrically in the plane of A. The magnetic flux linked with loop B is proportional to
Answer: (C) R2/3

9. Figure shows the variation of inductive reactance X₁ of two ideal inductors of inductance L₁ and L₂ with angular frequency w. The value of
Answer: (C) 3

10. The phase difference between electric field vec E and magnetic field vec B in an electromagnetic wave propagating along z-axis is
Answer: (A) Zero

11. A coil of N turns is placed in a magnetic field such that B is perpendicular to the plane of the coal vec R changes with time as B=B0 cos (2πt/T) where T is time period. The magnitude of emf induced in the coil will be maximum at
Answer: (C) t = nT/2

12. In Balmer series of hydrogen atom, as the wavelength of spectral lines decreases, they appear

Answer: (B) further apart and stronger in intensity.

13. Assertion (A): Electrons are ejected from the surface of zinc when it is irradiated by yellow light.
Reason (R): Energy associated with a photon of yellow light is more than the work function of zinc.

Answer:(C) If Assertion (A) is true and Reason (R) is false.

14. Assertion (A): The temperature coefficient of resistance is positive for metals and negative for p-type semiconductors.
Reason (R): The charge carriers in metals are negatively charged, whereas the majority charge carriers in p-type semiconductors are positively charged.

Answer: (A) If both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

15. Assertion (A): When electrons drift in a conductor, it does not mean that all free electrons in the conductor are moving in the same direction.
Reason (R): The drift velocity is superposed over large random velocities of electrons.

Answer:(A) If both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

16. Assertion (A): In interference and diffraction of light, light energy reduces in one region producing a dark fringe. It increases in another region and produces a bright fringe.
Reason (R): This happens because energy is not conserved in the phenomena of interference and diffraction.

Answer: (B) If both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

Class 12 Physics Answer Key 2024 SET 1 (55/5/1)

1. A battery supplies 0.9 A current through a 2 Ω resistor and 0.3 A current through a 7 Ω resistor when connected one by one. The internal resistance of the battery is:

(A) 2Ω
(B) 1.2Ω
(C) 1Ω
(D) 0.5Ω

Answer: (D) 0.5Ω

2. A particle of mass m and charge q describes a circular path of radius R in a magnetic field. If its mass and charge were 2 m and q/2 respectively, the radius of its path would be:

(A) R/4
(B) R/2
(C) 2R
(D) 4R
Answer: (C) 2R

3. Which of the following pairs is that of paramagnetic materials?

(A) Copper and Aluminium
(B) Sodium and Calcium
(C) Lead and Iron
(D) Nickel and Cobalt
Answer: (D) Nickel and Cobalt

4. A galvanometer of resistance 50 Ω is converted into a voltmeter of range (0 – 2V) using a resistor of 1.0 kΩ. If it is to be converted into a voltmeter of range (0 – 10 V), the resistance required will be

(A) 4.8 kΩ
(B) 5.0 kΩ
(C) 5.2 kΩ
(D) 5.4 kΩ

Answer: (C) 5.2 kΩ

5. Two coils are placed near each other. When the current in one coil is changed at the rate of 5 A/s, an emf of 2 mV is induced in the other. The mutual inductance of the two coils is

(A) 0.4 mH
(B) 2.5 mH
(C) 10 mH
(D) 2.5 H

Answer: (A) 0.4 mH

6. The electromagnetic waves used to purify water are
(A) Infrared rays
(B) Ultraviolet rays
(C) X-rays
(D) Gamma rays

Answer: (B) Ultraviolet rays

7. The focal lengths of the objective and the eyepiece of a compound microscope are 1 cm and 2 cm respectively. If the tube length of the microscope is 10 cm, the magnification obtained by the microscope for most suitable viewing by relaxed eye is:
(A) 250
(B) 200
(C) 150
(D) 125

8. The variation of the stopping potential (Vo) with the frequency (u) of the incident radiation for four metals A, B, C and D is shown in the figure. For the same frequency of incident radiation producing photo-electrons in all metals, the kinetic energy of photo-electrons will be maximum for metal

(A) A
(B) B
(C) C
(D) D

Answer:

9. The energy of an electron in the ground state of hydrogen atom is -13.6 eV. The kinetic and potential energy of the electron in the first excited state will be
(A) -13.6 eV, 27.2 eV
(B) -6.8 eV, 13,6 eV
(C) -3.4 eV, -6.8 eV
(D) 6.8 eV, -3.4 eV

Answer:

10. A Young’s double-slit experimental set up is kept in a medium of refractive index (4/3). Which maximum in this case will coincide with the 6th maximum obtained if the medium is replaced by air
(A) 4th
(B) 6th
(C) 8th
(D) 10th

11. The potential energy between two nucleons inside a nucleus is minimum at a distance of about
(A) 0.8 fm
(B) 1.6 fm
(C) 2.0 fm
(D) 2.8 fm

12. A pure Si crystal having 5 x 1028 atoms m³ is dopped with 1 ppm concentration of antimony. If the concentration of holes in the doped crystal is found to be 4.5 x 109 m-3, the concentration (in m³) of intrinsic charge carriers in Si crystal is about
(A) 1.2 × 1015
(C) 3.0 x 1015
(B) 1.5 x 1016
(D) 2.0 × 1016

Class 12 Physics Answer Key 2024 SET 3 (55/2/3)

SECTION-A

1.

(A) √3

(B) 1/√3

(C) 3

(D) 1/3

Answer: (D) 1/3

2. Electrons drift with speed Vd in a conductor with potential difference V across its ends. If V is reduced to V/2, their drift speed will become:
(A) Vd/2
(B) Vd
(C) 2Vd
(D) 4Vd

Answer: (A) Vd/2

3. The emf induced in a coil rotating in a magnetic field does not depend upon the following
(A) Area of the coil
(B) Resistance of the Coil
(C) Number of Turns in the coil
(D) Angular speed of rotation of the coil

Answer: (B) Resistance of the Coil

4. A circular coil of radius 10 cm is placed in a magnetic field В = (1.0 Î + 0.5j) mT such that the outward unit vector normal to the surface of the coil is (0.6 Î + 0•8j). The magnetic flux linked with the coil is :

(A) 0.314 μWb

(B) 3.14 μWb

(C) 31.4 μWb

(D) 1.256 μWb

5. Which of the following quantity/quantities remains the same in the primary and secondary coils of an ideal transformer?

Current, Voltage, Power, Magnetic flux

(A) Current only
(B) Voltage only
(C) Power only
(D) Magnetic flux and Power both

Answer: (D) Magnetic flux and Power both

6. In an AC circuit, the instantaneous values of current (in A) and voltage (in V) are I = 5 sin ωt and E = 200 cos (ωt + Π/3) respectively. The phase difference between voltage and current at any instant is :

(A) 5Π/6

(B) 5Π/4

(C) 5Π/2

(D) 3Π/2

Answer: (A) 5Π/6

7. In four regions I, II, III and IV, the magnetic field is given by :
I. By = Bo sin kz

II. By = Bo cos kz

III. By = Bo sin (kz- wt)

IV. By – Bo sin kz + Bo cos kz

The electromagnetic wave will exist in the region :
(A) IV
(C) III
(B)I
(D)II

Answer: (C) III

8. The momentum (in SI units) associated with a photon of energy 1.5 eV is:
(A) 4 × 10-27
(C) 2 × 10-30
(B) 8 × 10-28
(D) 6 × 10-29

Answer:

9. An n-type semiconducting Si is obtained by doping intrinsic Si with :
(A) Al
(C) P
(B) B
(D) In

Answer: (C) P

10. Energy levels A, B and C of an atom correspond to increasing values of energy i.e. EA< EB < EC. Let λ1, λ2 and λ3 be the wavelengths of radiation corresponding to the transitions C to B, B to A and C to A, respectively. The correct relation between λ1, λ2 and λ3 is :

11. When a p-n junction diode is subjected to reverse biasing :
(A) the barrier height decreases and the depletion region widens.
(B) the barrier height increases and the depletion region widens
(C) the barrier height decreases and the depletion region shrinks
(D) the barrier height increases and the depletion region shrinks.

Answer: (B) the barrier height increases and the depletion region widens

12. An alpha particle approaches a gold nucleus in Geiger-Marsden experiment with kinetic energy K. It momentarily stops at a distance d from the nucleus and reverses its direction. Then d is proportional to :

(A) 1/√K

(B) √K

(C) 1/K

(D) K

Answer: (C) 1/K

Questions number 13 to 16 are Assertion (A) and Reason (R) type questions. Two statements are given — one labeled Assertion (A) and the other labeled Reason (R). Select the correct answer from the codes (A), (B), (C) and (D) as given below.
(A) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
(B) Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
(C) Assertion (A) is true, but Reason (R) is false.
(D) Assertion (A) is false and Reason (R) is also false.

13. Assertion (A): An electron and a proton enter with the same momentum P in a magnetic field B such that P ⊥ B. Then both describe a circular path of the same radius.
Reason (R) : The radius of the circular path described by the charged particle (charge q, mass m) moving in the magnetic field B is given by r = mv/qB

14. Assertion (A): The magnifying power of a compound microscope is negative.
Reason (R) : The final image formed is erect with respect to the object.

15. Assertion (A) : Lenz’s law is a consequence of the law of conservation of energy.
Reason (R) : There is no power loss in an ideal inductor.

16. Assertion (A): Photoelectric current increases with an increase in intensity of incident radiation, for a given frequency of incident radiation and the accelerating potential.
Reason (R) : Increase in the intensity of incident radiation results in an increase in the number of photoelectrons emitted per second and hence an increase in the photocurrent,

CBSE Class 12 Physics Exam Analysis 2024

As per the students, “The CBSE Class 12th physics board exam was moderately tough. Students studied a lot but still found it hard to answer some questions. The numerical problems were especially tricky. They tried their best to remember all the formulas but got confused during the exam. Overall, it was a great paper.” Almost all the questions in the Physics question paper were from NCERT. Students disclosed that the question paper pattern was on the line of the official CBSE sample paper, and nothing was asked out of the prescribed syllabus of Physics.

• The overall CBSE Class 12th Physics Question Paper 2024 was Moderately tough.
• The numerical problems in the physics paper were especially tricky.
• The derivations and practical-based questions were the parts of the paper that were time-consuming.
• It included a good mix of theoretical and application-based questions

Whereas as per the expert review, “The CBSE Class 12 Physics paper today i.e., March 04, 2024 was well-balanced and followed the syllabus.” The difficulty level seemed moderate, and most questions were familiar with clear instructions. t included a good mix of theoretical and application-based questions, allowing students to showcase their understanding of concepts and problem-solving skills.

Class 12 Physics Exam Paper Analysis 2024

After the conduction of the exam, all the students who appeared in the Class 12 Physics Exam 2024 for SET 1, 2, 3, 4 can check the live Class 12 Physics Exam Analysis 2024 by Adda247. Watch the video.

Class 12 Physics Question Paper 2024 PDF Download

The Central Board of Secondary Education has conducted the Class 12 Physics Board Exam 2024 on March 04, 2024. The CBSE Board Question Papers are valuable resources as after the successful conduction of the exam, these question papers help the students to evaluate their performance in the exams. These question papers will help the students preparing to appear in the class 12th exams next year to provide an overview of the question paper, and the types of questions asked in the examination. The direct link to download the CBSE Class 12 Physics Question Paper 2024 PDF has been shared here.

CBSE Class 12 Physics Question Paper 2024 PDF
Class 12 Physics Exam Paper 2024 SET	Question Paper Link
SET 1	Class 12 Physics SET 1 Question Paper 2024
SET 2	Class 12 Physics SET 2 Question Paper 2024
SET 3	Class 12 Physics Question Paper 2024 SET 3

Class 12 Physics Answer Key 2024 PDF Download

All the students who appeared in the Class 12 Physics exam today i.e., March 04, 2024 can able to predict their marks via CBSE Class 12 Physics Answer Key 2024. Our subject expert’s faculty released the specially designed answer key for the questions that are asked in the CBSE Class 12 Physics Exam. All the students who appeared for the CBSE Class 12th Physics Board Exam 2024 will be able to check the complete CBSE Class 12 Physics Answer Key 2024 PDF from the direct link that has been shared in our article.

 

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