Practice Questions

Q15. As per the given graph, choose the correct representation for curve 𝐴 and curve 𝐵 {Where 𝑋𝐶= Reactance of pure capacitive circuit connected with A.C. source 𝑋𝐿= Reactance of pure inductive circuit connected with A.C. source 𝑅= Impedance of pure resistive circuit connected with A.C. source 𝑍= Impedance of the 𝐿𝐶𝑅 series circuit } (1) 𝐴= 𝑋𝐶, 𝐵= 𝑅 (2) 𝐴= 𝑋𝐿, 𝐵= 𝑅 (3) 𝐴= 𝑋𝐿, 𝐵= 𝑍 (4) 𝐴= 𝑋𝐶, 𝐵= 𝑋𝐿

Q15.If →𝐸 and →𝐾 represent electric field and propagation vectors of the EM waves in vacuum, then magnetic field vector is given by: (𝜔- angular frequency) 1 → → → → (1) 𝐾× 𝐸 (2) 𝜔𝐸× 𝐾 𝜔 (3) 𝜔→𝐾× →𝐸 (4) →𝐾× →𝐸

Q15.A monochromatic light wave with wavelength 𝜆1 and frequency 𝜈1 in air enters another medium. If the angle of incidence and angle of refraction at the interface are 45° and 30° respectively, then the wavelength 𝜆2 and frequency 𝜈2 of the refracted wave are: (1) 𝜆2 = √2𝜆1, 𝜈2 = 𝜈1 (2) 𝜆2 = 𝜆1, 𝜈2 = 1 √2𝜈1 (3) 𝜆2 = 𝜆1, 𝜈2 = √2𝜈1 (4) 𝜆2 = 1 𝜈2 = 𝜈1 √2𝜆1,

Q15.Two polaroids 𝐴 and 𝐵 are placed in such a way that the pass-axis of polaroids are perpendicular to each other. Now, another polaroid 𝐶 is placed between 𝐴 and 𝐵 bisecting angle between them. If intensity of unpolarised light is 𝐼0 then intensity of transmitted light after passing through polaroid 𝐵 will be : (1) 𝐼0 (2) 𝐼0 4 2 𝐼0 (3) (4) Zero 8

Q15.If V is the gravitational potential due to sphere of uniform density on its surface, then its value at the centre of sphere will be: (1) 4 V (2) V 3 2 (3) V (4) 3V 2

Q15.In a series 𝐿𝑅 circuit with 𝑋𝐿= 𝑅, power factor is 𝑃1. If a capacitor of capacitance 𝐶 with 𝑋𝐶= 𝑋𝐿 is added to the circuit the power factor becomes 𝑃2. The ratio of 𝑃1 to 𝑃2 will be : (1) 1: 3 (2) 1: √2 (3) 1: 1 (4) 1: 2

Q15.Considering a group of positive charges, which of the following statements is correct? (1) Net potential of the system cannot be zero at a (2) Net potential of the system at a point can be zero point but net electric field can be zero at that but net electric field can't be zero at that point point (3) Both the net potential and the net field can be (4) Both the net potential and the net electric field zero at a point cannot be zero at a point

Q15.In a cuboid of dimension 2L × 2L × L , a charge q is placed at the centre of the surface S having area of 4L2 . The flux through the opposite surface to S is given by (1) q (2) q 12∈0 3∈0 (3) q (4) q 2∈0 6∈0

Q15.Two charges of each magnitude 0. 01 C and separated by a distance of 0. 4 mm constitute an electric dipole. If → → the dipole is placed in an uniform electric field E of 10 dyne ⋅C−1 making 30∘ angle with E, the magnitude of torque acting on dipole is: (1) 4. 0 × 10−10 N m (2) 1. 0 × 10−8 N m (3) 1. 5 × 10−9 N m (4) 2. 0 × 10−10 N m

Q15.An organ pipe 40 cm long is open at both ends. The speed of sound in air is 360 m s−1 . The frequency of the second harmonic is _ ________ Hz.

Q15.Given below are two statements: Statement I : Out of microwaves, infrared rays and ultraviolet rays, ultraviolet rays are the most effective for the emission of electrons from a metallic surface JEE Main 2023 (13 Apr Shift 2) JEE Main Previous Year Paper Statement II : Above the threshold frequency, the maximum kinetic energy of photoelectrons is inversely proportional to the frequency of the incident light In the light of above statements, choose the correct answer from the options given below (1) Statement I is false but Statement II is true (2) Statement I is true but Statement II is false (3) Both Statement I and Statement II are true (4) Both Statement I and Statement II are false

Q15.A 12 V battery connected to a coil of resistance 6 Ω through a switch, drives a constant current in the circuit. The switch is opened in 1 ms. The emf induced across the coil is 20 V. The inductance of the coil is : (1) 10 mH (2) 8 mH (3) 5 mH (4) 12 mH

Q15.Match List I with List II List I List II A Troposphere I Approximate 65 −75 km over Earth’s surface B E-Part of Stratosphere II Approximate 300 km over Earth’s surface C F2 -Part of Thermosphere III Approximate 10 km over Earth’s surface D D-Part of Stratosphere IV Approximate 100 km over Earth’s surface Choose the correct answer from the options given below : (1) A-III, B-IV, C-II, D-I (2) A-I, B-II, C-IV, D-III (3) A-I, B-IV, C-III, D-II (4) A-III, B-II, C-I, D-IV

Q16.Experimentally it is found that 12. 8 eV energy is required to separate a hydrogen atom into a proton and an electron. So the orbital radius of the electron in a hydrogen atom is 9 × 10−10 m. x The value of the x is: _____. ( 1 eV = 1. 6 × 10−19 J, 1 = 9 × 109 Nm2C2 and electronic charge = 1. 6 × 10−19 C) 4πε0

Q16.As shown in figure, a cuboid lies in a region with electric field E = 2x2ˆi −4yˆj + 6ˆk N C−1 . The magnitude of charge within the cuboid is nε0 C. The value of n is ______ (if dimension of cuboid is 1 × 2 × 3 m3 )

Q16.A parallel plate capacitor has plate area 40 cm2 and plates separation 2 mm . The space between the plates is filled with a dielectric medium of a thickness 1 mm and dielectric constant 5 . The capacitance of the system is: (1) 24ε0 F (2) 103 ε0 F (3) 10 3 ε0 F (4) 10ε0 F

Q16.For a charged spherical ball, electrostatic potential inside the ball varies with r as V = 2ar2 + b. Here, a and b are constant and r is the distance from the center. The volume charge density inside the ball is −λaε. The value of λ is ______. ε = permittivity of medium.

Q16.The variation of stopping potential V0 as a function of the frequency ( 𝜈) of the incident light for a metal is shown in figure. The work function of the surface is JEE Main 2023 (10 Apr Shift 2) JEE Main Previous Year Paper (1) 2 . 98 eV (2) 2 . 07 eV (3) 1 . 36 eV (4) 18 . 6 eV

Q16.Match List-I with List II of Electromagnetic waves with corresponding wavelength range: List I List II (A) Microwave (I) 400 nm to 1 nm (B) Ultraviolet (II) 1 nm to 10–3 nm (C) X -Ray (III) 1 mm to 700 nm (D) Infra-red (IV) 0. 1 m to 1 mm Choose the correct answer from the options given below: (1) (A) −(IV), (B) −(I), (C) −(II), (D) −(III) (2) (A) −(IV), (B) −(I), (C) −(III), (D) −(II) (3) (A) −(IV), (B) −(II), (C) −(I), (D) −(III) (4) (A) −(I), (B) −(IV), (C) −(II), (D) −(III)

Q16.Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Two metallic spheres are charged to the same potential. One of them is hollow and another is solid, and both have the same radii. Solid sphere will have lower charge than the hollow one. Reason R : Capacitance of metallic spheres depend on the radii of spheres. In the light of the above statements, choose the correct answer from the options given below. (1) A is false but R is true (2) Both A and R are true and R is the correct explanation of A (3) A is true but R is false (4) Both A and R are true but R is not the correct explanation of A

Q16.Graphical variation of electric field due to a uniformly charged insulating solid sphere of radius R, with distance r from the centre O is represented by: JEE Main 2023 (08 Apr Shift 1) JEE Main Previous Year Paper (1) Dig (2) (3) (4)

Q16.A train blowing a whistle of frequency 320 Hz approaches an observer standing on the platform at a speed of 66 m s−1 . The frequency observed by the observer will be (given speed of sound = 330 m s−1 ) ______ Hz.

Q16.Given below are two statements : Statement I : If the Brewster's angle for the light propagating from air to glass is 𝜃𝐵, then Brewster's angle for the light propagating from glass to air is 𝜋 - 𝜃𝐵. 2 Statement II : The Brewster's angle for the light propagating from glass to air is tan-1𝜇g, where 𝜇g is the refractive index of glass. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statements I and Statement II are true. (2) Statement I is true but Statement II is false. (3) Both Statement I and Statement II are false. (4) Statement I is false but Statement II is true.

Q16.An object is placed at a distance of 12 cm in front of a plane mirror. The virtual and erect image is formed by the mirror. Now the mirror is moved by 4 cm towards the stationary object. The distance by which the position of image would be shifted, will be (1) 4 cm towards mirror (2) 8 cm towards mirror (3) 8 cm away from mirror (4) 2 cm towards mirror

Q16.A capacitor of capacitance C is charged to a potential V . The flux of the electric field through a closed surface enclosing the positive plate of the capacitor is: (1) CV (2) Zero ε0 (3) 2 CV (4) CV ε0 2ε0