Practice Questions

Q24.A particle performs simple harmonic motion with amplitude 𝐴. Its speed is increased to three times at an 2𝐴 𝑛𝐴 instant when its displacement is . The new amplitude of motion is . The value of 𝑛 is _____. 3 3

Q24.Two open organ pipes of lengths 60 cm and 90 cm resonate at 6th and 5th harmonics respectively. The difference of frequencies for the given modes is _______ Hz . (Velocity of sound in air = 333 m/s )

Q24.The position, velocity and acceleration of a particle executing simple harmonic motion are found to have magnitudes of 4 m, 2 ms−1 and 16 ms−2 at a certain instant. The amplitude of the motion is √x, m where x is ________

Q24.The time period of simple harmonic motion of mass 𝑀 in the given figure is 𝜋√ 𝛼𝑀5𝐾, where the value of _______. JEE Main 2024 (31 Jan Shift 2) JEE Main Previous Year Paper

Q25.Suppose a uniformly charged wall provides a uniform electric field of 2 × 104 N C-1 normally. A charged particle of mass 2 g being suspended through a silk thread of length 20 cm and remain stayed at a distance 1 of 10 cm from the wall. Then the charge on the particle will be 𝜇C where 𝑥= ________ [use √x 𝑔= 10 m s-2]

Q25.A particle of mass 0.50 kg executes simple harmonic motion under force F = −50 (Nm−1)x. The time period of oscillation is 35 x s. The value of x is _______ (Given π = 227 )

Q25.At the centre of a half ring of radius R = 10 cm and linear charge density 4nCm−1 , the potential is xπV . The value of x is _______ JEE Main 2024 (09 Apr Shift 1) JEE Main Previous Year Paper

Q25.If the net electric field at point P along Y axis is zero, then the ratio of q2 is 8 , where x = _____. q3 5√x

Q25.Two identical charged spheres are suspended by strings of equal lengths. The strings make an angle 𝜃 with each other. When suspended in water the angle remains the same. If density of the material of the sphere is 1 . 5 g / cc, the dielectric constant of water will be ______. (Take density of water = 1 g / cc)

Q25.An infinite plane sheet of charge having uniform surface charge density +σsC/m2 is placed on x −y plane. Another infinitely long line charge having uniform linear charge density +λeC/m is placed at z = 4 m plane and parallel to y-axis. If the magnitude values |σs| = 2 |λe| then at point (0, 0, 2), the ratio of magnitudes of electric field values due to sheet charge to that of line charge is π√n : 1. The value of n is_______.

Q25.The distance between charges +𝑞 and -𝑞 is 2𝑙 and between +2𝑞 and -2𝑞 is 4𝑙. The electrostatic potential at point 𝑃 at a distance 𝑟 from centre 𝑂 is -𝛼𝑞𝑙 × 109 V, where the value of 𝛼 is ______. (Use 𝑟2 1 = 9 × 109 N m2 C-2) 4𝜋𝜀0 2

Q25.A parallel plate capacitor of capacitance 12.5pF is charged by a battery connected between its plates to potential difference of 12.0 V. The battery is now disconnected and a dielectric slab (ϵr = 6) is inserted between the plates. The change in its potential energy after inserting the dielectric slab is _____ 10−12 J.

Q25.A parallel plate capacitor with plate separation 5 mm is charged up by a battery. It is found that on introducing a dielectric sheet of thickness 2 mm, while keeping the battery connections intact, the capacitor draws 25% more charge from the battery than before. The dielectric constant of the sheet is ____.

Q25.The electric field between the two parallel plates of a capacitor of 1.5μF capacitance drops to one third of its initial value in 6.6μs when the plates are connected by a thin wire. The resistance of this wire is _____ Ω . (Given, log 3 = 1.1 )

Q25.The electric field at point p due to an electric dipole is E. The electric field at point R on equitorial line will be E . The value of x : x

Q25.In the given circuit, the current flowing through the resistance 20 Ω is 0. 3 A, while the ammeter reads 0. 9 A. The value of R1 is _____ Ω .

Q25.A capacitor of capacitance C and potential V has energy E. It is connected to another capacitor of capacitance 2C and potential 2V . Then the loss of energy is x3 E , where x is _______.

Q25.Three infinitely long charged thin sheets are placed as shown in figure. The magnitude of electric field at the point P is xσ . The value of x is _______ (all quantities are measured in SI units). ϵo JEE Main 2024 (06 Apr Shift 1) JEE Main Previous Year Paper

Q26.An electric field →E = (2x^i)NC −1 exists in space. A cube of side 2 m is placed in the space as per figure given below. The electric flux through the cube is ______ Nm2/C. JEE Main 2024 (09 Apr Shift 2) JEE Main Previous Year Paper

Q26.The current flowing through the 1Ω resistor is 10n A. The value of n is _________

Q26.Equivalent resistance of the following network is ________ 𝛺.

Q26.In the experiment to determine the galvanometer resistance by half-deflection method, the plot of 1/θ vs the resistance (R) of the resistance box is shown in the figure. The figure of merit of the galvanometer is _____ ×10−1 A/ division. [The source has emf 2V]

Q26.A wire of resistance R and radius r is stretched till its radius became r/2. If new resistance of the stretched wire is xR, then value of x is _______ →

Q26.In an electrical circuit drawn below the amount of charge stored in the capacitor is _______ μC .

Q26.Resistance of a wire at 0∘C, 100∘C and t∘C is found to be 10Ω, 10.2Ω and 10.95Ω respectively. The temperature t in Kelvin scale is _________