Practice Questions

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.A Carnot engine operating between two reservoirs has efficiency 1 . When the temperature of cold reservoir 3 raised by x , its efficiency decreases to 1 . The value of x , if the temperature of hot reservoir is 99° C , will be 6 (1) 16. 5 K (2) 33 K (3) 66 K (4) 62 K

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.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.Two simple harmonic waves having equal amplitudes of 8 cm and equal frequency of 10 Hz are moving along the same direction. The resultant amplitude is also 8 cm. The phase difference between the individual waves is _____ degree.

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.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

Q14.At a given point of time the value of displacement of a simple harmonic oscillator is given as y = A cos(30°). If amplitude is 40 cm and kinetic energy at that time is 200 J, the value of force constant 1. 0 × 10x N m–1 . The value of x is _____.

Q14.The distance between two consecutive points with phase difference of 60° in a wave of frequency 500 Hz is 6. 0 m . The velocity with which wave is travelling is ______ km s−1 .

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 guitar string of length 90 cm vibrates with a fundamental frequency of 120 Hz. The length of the string producing a fundamental of 180 Hz will be _____ cm

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.The engine of a train moving with speed 10 m s−1 towards a platform sounds a whistle at frequency 400 Hz . The frequency heard by a passenger inside the train is: (Neglect air speed. Speed of sound in air = 330 m s−1 ) (1) 400 Hz (2) 200 Hz (3) 412 Hz (4) 388 Hz

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.Match the List-I with List-II. List I List II A AC generator I Presence of both L and C B Transformer II Electromagnetic Induction C Resonance phenomenon to occur III Quality factor D Sharpness of resonance IV Mutual Inductance Choose the correct answer from the options given below: (1) A-IV, B-II, C-I, D-III (2) A-II, B-I, C-III, D-IV (3) A-II, B-IV, C-I, D-III (4) A-IV, B-III, C-I, D-II

Q14.Given below are two statements: Statement I : An AC circuit undergoes electrical resonance if it contains either a capacitor or an inductor. Statement II: An AC circuit containing a pure capacitor or a pure inductor consumes high power due to its non- zero power factor. 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 false (4) Both Statement I and Statement II are true

Q14.The energy of an electromagnetic wave contained in a small volume oscillates with (1) Double the frequency of the wave (2) The frequency of the wave (3) Half the frequency of the wave (4) Zero frequency

Q14.In the given circuit, the current I through the battery will be (1) 2. 5 A (2) 1 A (3) 2 A (4) 1. 5 A

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.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 conducting loop of radius cm is placed perpendicular to a uniform magnetic field of 0 . 5 T. The √𝜋 magnetic field is decreased to zero in 0 . 5 s at a steady rate. The induced emf in the circular loop at 0 . 25 s is: (1) emf = 1mV (2) emf = 10mV (3) emf = 100mV (4) emf = 5mV

Q15.A uniform electric field of 10 N C−1 is created between two parallel charged plates (as shown in figure). An electron enters the field symmetrically between the plates with a kinetic energy 0. 5 eV. The length of each plate is 10 cm. The angle (θ) of deviation of the path of electron as it comes out of the field is ______(in degree). JEE Main 2023 (25 Jan Shift 1) JEE Main Previous Year Paper

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