Practice Questions

Q15. List-I List-II EM-Wave Wavelength Range (A) Infra-red (I) < 10−3 nm Match List-I with List-II : (B) Ultraviolet (II) 400 nm to 1 nm (C) X-rays S (III) 1 mm to 700 nm (D) Gamma rays (IV) 1 nm to 10−3 nm (1) (A)-(III), (B)-(II), (C)-(IV), (D)-(I) (2) (A)-(II), (B)-(I), (C)-(IV), (D)-(III) (3) (A)-(IV), (B)-(III), (C)-(II), (D)-(I) (4) (A)-(I), (B)-(III), (C)-(II), (D)-(IV)

Q15.Given below are two statements: Statement I: Electromagnetic waves carry energy as they travel through space and this energy is equally shared by the electric and magnetic fields. Statement II: When electromagnetic waves strike a surface, a pressure is exerted on the surface. In the light of the above statements, choose the most appropriate answer from the options given below: (1) Statement I is incorrect but Statement II is (2) Both Statement I and Statement II are correct correct (3) Both Statement I and Statement II are incorrect (4) Statement I is correct but Statement II is incorrect

Q15.A plane electromagnetic wave of frequency 35 MHz travels in free space along the X -direction. At a → particular point (in space and time) E = 9. 6ˆj V m−1 . The value of magnetic field at this point is: (1) 3. 2 × 10−8ˆk T (2) 3. 2 × 10−8ˆi (3) 9. 6ˆj T (4) 9. 6 × 10−8ˆk T

Q15.If the total energy transferred to a surface in time 𝑡 is 6 . 48 × 105 J, then the magnitude of the total momentum delivered to this surface for complete absorption will be : (1) 2 . 46 × 10-3 kg m s-1 (2) 2 . 16 × 10-3 kg m s-1 (3) 1 . 58 × 10-3 kg m s-1 (4) 4 . 32 × 10-3 kg m s-1

Q15.In finding out refractive index of glass slab the following observations were made through travelling microscope 50 vernier scale division = 49MSD; 20 divisions on main scale in each cm For mark on paper JEE Main 2024 (06 Apr Shift 2) JEE Main Previous Year Paper MSR = 8.45 cm, VC = 26 For mark on paper seen through slab MSR = 7.12 cm, V C = 41 For powder particle on the top surface of the glass slab MSR = 4.05 cm, VC = 1 (MSR = Main Scale Reading, VC = Vernier Coincidence) Refractive index of the glass slab is : (1) 1.52 (2) 1.35 (3) 1.42 (4) 1.24

Q15.Two conducting circular loops A and B are placed in the same plane with their centers coinciding as shown in figure. The mutual inductance between them is : (1) μ0πb2 (2) μo ⋅b2a 2π 2a (3) μ0 2π ⋅a2b (4) μ0πa22b

Q15.UV light of 4.13eV is incident on a photosensitive metal surface having work function 3.13eV. The maximum kinetic energy of ejected photoelectrons will be: (1) 4.13eV (2) 3.13eV (3) 1eV (4) 7.26eV

Q15.A transformer has an efficiency of 80% and works at 10 V and 4 kW . If the secondary voltage is 240 V, then the current in the secondary coil is: (1) 1 . 59 A (2) 13 . 33 A (3) 1 . 33 A (4) 15 . 1 A

Q15.In series LCR circuit, the capacitance is changed from 𝐶 to 4𝐶. To keep the resonance frequency unchanged, the new inductance should be : 1 (1) reduced by 4𝐿 (2) increased by 2𝐿 (3) reduced by 3 (4) increased to 4𝐿 4𝐿 o

Q15.An object is placed in a medium of refractive index 3. An electromagnetic wave of intensity 6 × 108 W m-2 falls normally on the object and it is absorbed completely. The radiation pressure on the object would be (speed of light in free space = 3 × 108 m s-1 ): (1) 36 N m-2 (2) 18 N m-2 (3) 6 N m-2 (4) 2 N m-2

Q15.Electromagnetic waves travel in a medium with speed of 1.5 × 108 m s−1 . The relative permeability of the medium is 2.0 . The relative permittivity will be: (1) 2 (2) 4 (3) 5 (4) 1

Q15.Arrange the following in the ascending order of wavelength: A. Gamma rays (λ1) B. x - rays (λ2) C. Infrared waves (λ3) D. Microwaves (λ4) Choose the most appropriate answer from the options given below (1) λ4 < λ3 < λ1 < λ2 (2) λ2 < λ1 < λ4 < λ3 (3) λ1 < λ2 < λ3 < λ4 (4) λ4 < λ3 < λ2 < λ1

Q15.Critical angle of incidence for a pair of optical media is 45∘ . The refractive indices of first and second media are in the ratio: (1) 1 : √2 (2) √2 : 1 (3) 2 : 1 (4) 1 : 2

Q15.A plane electromagnetic wave propagating in x-direction is described by Ey = (200 V m−1) sin[1. 5 × 107t −0. 05x]; The intensity of the wave is : (Use ϵ0 = 8. 85 × 10−12 C2 N−1 m−2 ) (1) 35. 4 W m−2 (2) 53. 1 W m−2 (3) 26. 6 W m−2 (4) 106. 2 W m−2

Q15.A coil is placed perpendicular to a magnetic field of 5000 T. When the field is changed to 3000 T in 2 s, an induced emf of 22 V is produced in the coil. If the diameter of the coil is 0 . 02 m, then the number of turns in the coil is: (1) 7 (2) 70 (3) 35 (4) 140

Q16.A hydrogen atom in ground state is given an energy of 10.2eV. How many spectral lines will be emitted due to transition of electrons? (1) 6 (2) 3 (3) 10 (4) 1

Q16.A monochromatic light of wavelength 6000 A is incident on the single slit of width 0 . 01 mm. If the diffraction pattern is formed at the focus of the convex lens of focal length 20 cm, the linear width of the central maximum is : (1) 60 mm (2) 24 mm (3) 120 mm (4) 12 mm

Q16.An alternating voltage of amplitude 40 V and frequency 4kHz is applied directly across the capacitor of 12μF. The maximum displacement current between the plates of the capacitor is nearly : (1) 10 A (2) 12 A (3) 8 A (4) 13 A

Q16.If the distance between object and its two times magnified virtual image produced by a curved mirror is 15 cm , the focal length of the mirror must be : (1) 15 cm (2) −12 cm (3) −10 cm (4) 103 cm

Q16.For the photoelectric effect, the maximum kinetic energy 𝐸𝑘 of the photoelectrons is plotted against the frequency ( 𝑣) of the incident photons as shown in figure. The slope of the graph gives (1) Ratio of Planck’s constant to electric charge (2) Work function of the metal (3) Charge of electron (4) Planck’s constant

Q16.The width of one of the two slits in a Young's double slit experiment is 4 times that of the other slit. The ratio of the maximum of the minimum intensity in the interference pattern is: (1) 1 : 1 (2) 4 : 1 (3) 9 : 1 (4) 16 : 1

Q16.If the refractive index of the material of a prism is cot( A2 ), where A is the angle of prism then the angle of minimum deviation will be (1) π −2 A (2) π2 −2 A (3) π −A (4) π2 −A JEE Main 2024 (27 Jan Shift 1) JEE Main Previous Year Paper

Q16.Given below are two statements : Statement (I) : When an object is placed at the centre of curvature of a concave lens, image is formed at the centre of curvature of the lens on the other side. Statement (II) : Concave lens always forms a virtual and erect image. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are true (2) Both Statement I and Statement II are false (3) Statement I is true but Statement II is false (4) Statement I is false but Statement II is true

Q16.The electric field in an electromagnetic wave is given by E = ^i40 cos ω(t −z/c)NC−1 . The magnetic field induction of this wave is (in SI unit) : (1) → →B = ^j40 cos ω(t −z/c) B = ^k 40C cos ω(t −z/c) (2) (3) → 40 (4) → 40 B = ^i C cos ω(t −z/c) B = ^j C cos ω(t −z/c)

Q16.A proton and an electron have the same de Broglie wavelength. If Kp and Ke be the kinetic energies of proton and electron respectively, then choose the correct relation : (1) Kp > Ke (2) Kp < Ke (3) Kp = Ke (4) Kp = Ke2