Practice Questions

Q13.A car P travelling at 20 m s−1 sounds its horn at a frequency of 400 Hz. Another car Q is travelling behind the first car in the same direction with a velocity 40 m s−1 . The frequency heard by the passenger of the car Q is approximately [Take, velocity of sound = 360 m s−1 ] (1) 421 Hz (2) 471 Hz (3) 485 Hz (4) 514 Hz

Q13.Given below are two statements: Statement I : The equivalent resistance of resistors in a series combination is smaller than least resistance used in the combination. Statement II : The resistivity of the material is independent of temperature. In the light of the above statements, choose the correct answer from the options given below: JEE Main 2023 (15 Apr Shift 1) JEE Main Previous Year Paper (1) Both Statement I and Statement II are false (2) Both Statement I and Statement II are true (3) Statement I is true but Statement II is false (4) Statement I is false but Statement II is true

Q13.A circular loop of radius 𝑅 is carrying current 𝑖 A. The ratio of magnetic field at the centre of circular loop and at a distance 𝑅 from the center of the loop on its axis is : (1) 1: 3√2 (2) 3√2: 2 (3) 2√2: 1 (4) 1: √2 JEE Main 2023 (24 Jan Shift 1) JEE Main Previous Year Paper 10

Q13.The induced emf can be produced in a coil by A. moving the coil with uniform speed inside uniform magnetic field B. moving the coil with non uniform speed inside uniform magnetic field C. rotating the coil inside the uniform magnetic field D. changing the area of the coil inside the uniform magnetic field Choose the correct answer from the options given below: (1) 𝐵 and 𝐶 only (2) 𝐴 and 𝐶 only (3) 𝐶 and 𝐷 only (4) 𝐵 and 𝐷 only

Q13.A massless square loop, of wire of resistance 10 Ω, supporting a mass of 1 g, hangs vertically with one of its sides in a uniform magnetic field of 103 G, directed outwards in the shaded region. A dc voltage 𝑉 is applied to the loop. For what value of 𝑉, the magnetic force will exactly balance the weight of the supporting mass of 1 g? (If sides of the loop = 10 cm, 𝑔= 10 m s-2) . JEE Main 2023 (30 Jan Shift 1) JEE Main Previous Year Paper 1 (1) 10V (2) 100 V (3) 1 V (4) 10 V

Q13.Find the magnetic field at the point P in figure. The curved portion is a semicircle connected to two long straight wires. JEE Main 2023 (01 Feb Shift 1) JEE Main Previous Year Paper 𝜇0𝑖 2 𝜇0𝑖 1 (1) 2𝑟1 + π (2) 2𝑟1 + π 𝜇0𝑖 1 1 𝜇0𝑖 1 1 (3) + (4) + 2𝑟 2 2π 2𝑟 2 π

Q13.Match List I with List II : List I List II AIsothermal I Work done by the gas decreases internal energy Process B Adiabatic Process II No change in internal energy The heat absorbed goes partly to increase internal energy and partly to do C Isochoric Process III work DIsobaric Process IVNo work is done on or by the gas Choose the correct answer from the options given below : (1) A-II, B-I, C-III, D-IV (2) A-II, B-I, C-IV, D-III (3) A-I, B-II, C-IV, D-III (4) A-I, B-II, C-III, D-IV

Q13.A simple pendulum with length 100 cm and bob of mass 250 g is executing S.H.M of amplitude 10 cm. The maximum tension in the string is found to be x N . The value of x is _____. 40

Q13.Which graph represents the difference between total energy and potential energy of a particle executing SHM vs its distance from mean position? JEE Main 2023 (13 Apr Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)

Q13.An electron is moving along the positive x-axis. If uniform magnetic field is applied parallel to the negative z- axis, then A.The electron will experience magnetic force along positive y-axis B.The electron will experience magnetic force along negative y-axis C.The electron will not experience any force in magnetic field D.The electron will continue to move along the positive x-axis E.The electron will move along circular path in magnetic field Choose the correct answer from the option given below: (1) A and E only (2) C and D only (3) B and E only (4) B and D only

Q13.Given below are two statements: Statement I: For diamagnetic substance -1 ≤x < 0, where x is the magnetic susceptibility. Statement II: Diamagnetic substance when placed in an external magnetic field, tend to move from stronger to weaker part of the field. In the light of the above statements, choose the correct answer from the options give below. (1) Both Statement I and Statement II are False (2) Statement I is correct but Statement II is false (3) Statement I is incorrect but Statement II is true (4) Both Statement I and Statement II are true

Q13.A bar magnet with a magnetic moment 5 . 0 A m2 is placed in parallel position relative to a magnetic field of 0 . 4 T. The amount of required work done in turning the magnet form parallel to antiparallel position relative to the field direction is ________. (1) 4 J (2) 1 J (3) 2 J (4) Zero

Q13.Let γ1 be the ratio of molar specific heat at constant pressure and molar specific heat at constant volume of a monoatomic gas and γ2 be the similar ratio of diatomic gas. Considering the diatomic gas molecule as a rigid rotator, the ratio γ1 is: γ2 (1) 27 (2) 35 35 27 (3) 25 (4) 21 21 25

Q13.If the r.m.s speed of chlorine molecule is 490 m s−1 at 27oC , the r.m.s speed of argon molecules at the same temperature will be (Atomic mass of argon = 39. 9 u , molecular mass of chlorine = 70. 9 u ) (1) 551. 7 m s−1 (2) 651. 7 m s−1 (3) 451. 7 m s−1 (4) 751. 7 m s−1

Q13.Given below are two statements: Statement I: If heat is added to a system, its temperature must increase. Statement II: If positive work is done by a system in a thermodynamic process, its volume must increase. In the light of the above statements, choose the correct answer from the options given below (1) Statement I is true but Statement II is false (2) Both Statement I and Statement II are false (3) Both Statement I and Statement II are true (4) Statement I is false but Statement II is true

Q14.A particle executes simple harmonic motion between x = –A and x = +A. If time taken by particle to go from x = 0 to A2 is 2 s; then time taken by particle in going from x = A2 to A is: (1) 3 s (2) 2 s (3) 1. 5 s (4) 4 s

Q14.The velocity of a particle executing SHM varies with displacement ( x) as 4v2 = 50–x2 . The time period of oscillations is x 7 s. The value of x is ______. [Take π = 227 ]

Q14.A person observes two moving trains, A reaching the station and B leaving the station with equal speed of 30 m s−1 . If both trains emit sounds with frequency 300 Hz, (Speed of sound : 330 m s−1 ) approximate difference of frequencies heard by the person will be : (1) 33 Hz (2) 55 Hz (3) 80 Hz (4) 10 Hz

Q14.A particle is executing simple harmonic motion (SHM). The ratio of potential energy and kinetic energy of the particle when its displacement is half of its amplitude will be (1) 1 : 1 (2) 1 : 3 (3) 2 : 1 (4) 1 : 4

Q14.The free space inside a current carrying toroid is filled with a material of susceptibility 2 × 10-2. The percentage increase in the value of magnetic field inside the toroid will be (1) 0 . 2% (2) 0 . 1% (3) 2% (4) 1%

Q14.A mass m attached to free end of a spring executes SHM with a period of 1 s. If the mass is increased by 3 kg the period of oscillation increases by one second, the value of mass m is ________ kg.

Q14.A particle of mass 250 g executes a simple harmonic motion under a periodic force F = (–25x) N. The particle attains a maximum speed of 4 m s−1 during its oscillation. The amplitude of the motion is ______ cm.

Q14.The displacement equations of two interfering waves are given by y1 = 10 sin (ωt + π3 ) cm, cm respectively. The amplitude of the resultant wave is _____ cm. y2 = 5[sin (ωt) + √3 cos ωt]

Q14.Choose the correct length (L) versus square of time period (T2) ) graph for a simple pendulum executing simple harmonic motion. JEE Main 2023 (01 Feb Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)

Q14.A wire of density 8 × 103 kg m−3 is stretched between two clamps 0. 5 m apart. The extension developed in the wire is 3. 2 × 10−4 m. If Y = 8 × 1010 N m−2 , the fundamental frequency of vibration in the wire will be _____ Hz