Practice Questions

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.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.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.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. 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)

Q16.A convex mirror of radius of curvature 30 cm forms an image that is half the size of the object. The object distance is : (1) −45 cm (2) 45 cm (3) −15 cm (4) 15 cm

Q16.For the thin convex lens, the radii of curvature are at 15 cm and 30 cm respectively. The focal length the lens is 20 cm. The refractive index of the material is : (1) 1.2 (2) 1.8 (3) 1.5 (4) 1.4

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.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.The electric field of an electromagnetic wave in free space is represented as →E = E0 cos(ωt −kz)ˆi corresponding magnetic induction vector will be : (1) → (2) → E0 B = E0C B = C cos(ωt −kz)ˆj cos(ωt −kz)ˆj (3) → (4) → E0 B = E0C + B = C + cos(ωt kz)ˆj cos(ωt kz)ˆj JEE Main 2024 (30 Jan Shift 1) JEE Main Previous Year Paper

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.In photoelectric experiment energy of 2.48eV irradiates a photo sensitive material. The stopping potential was measured to be 0.5 V. Work function of the photo sensitive material is : (1) 1.68eV (2) 2.48eV (3) 1.98eV (4) 0.5eV

Q16.When unpolarized light is incident at an angle of 60° on a transparent medium from air. The reflected ray is completely polarized. The angle of refraction in the medium is (1) 30° (2) 60° (3) 90° (4) 45°

Q16.If frequency of electromagnetic wave is 60 MHz and it travels in air along z direction then the corresponding electric and magnetic field vectors will be mutually perpendicular to each other and the wavelength of the wave in m is : (1) 2 . 5 (2) 10 (3) 5 (4) 2

Q16.In a plane EM wave, the electric field oscillates sinusoidally at a frequency of 5 × 1010 Hz and an amplitude of 50 V m – 1. The total average energy density of the electromagnetic field of the wave is : [Use 𝜀0 = 8 . 85 × 10 – 12 C2 N-1 m-2] (1) 1 . 106 × 10 – 8 J m – 3 (2) 4 . 425 × 10 – 8 J m – 3 (3) 2 . 212 × 10 – 8 J m – 3 (4) 2 . 212 × 10 – 10 J m – 3 𝐴

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.When a polaroid sheet is rotated between two crossed polaroids then the transmitted light intensity will be maximum for a rotation of : (1) 60° (2) 30° (3) 90° (4) 45°

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.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 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.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

Q17.Which of the following statement is not true about stopping potential (V0) ? (1) It is 1/ e times the maximum kinetic energy of (2) It increases with increase in intensity of the electrons emitted. incident light. (3) It depends on the nature of emitter material. (4) It depends upon frequency of the incident light.

Q17.When UV light of wavelength 300 nm is incident on the metal surface having work function 2.13eV, electron emission takes place. The stopping potential is: (Given hc = 1240eVnm ) (1) 1.5 V (2) 4.1 V (3) 2 V (4) 4 V

Q17.The de Broglie wavelengths of a proton and an 𝛼 particle are 𝜆 and 2𝜆 respectively. The ratio of the velocities of proton and 𝛼 particle will be : (1) 1 : 8 (2) 1 : 2 (3) 4 : 1 (4) 8 : 1

Q17.The diffraction pattern of a light of wavelength 400 nm diffracting from a slit of width 0. 2 mm is focused on the focal plane of a convex lens of focal length 100 cm. The width of the 1st secondary maxima will be : (1) 2 mm (2) 2 cm (3) 0. 02 mm (4) 0. 2 mm