Practice Questions

Q12.In an Isothermal change, the change in pressure and volume of a gas can be represented for three different temperature; T3 > T2 > T1 as: JEE Main 2023 (24 Jan Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)

Q12.An air bubble of diameter 6 mm rises steadily through a solution of density 1750 kg m−3 at the rate of 0. 35 cm s−1 . The co-efficient of viscosity of the solution (neglect density of air) is ________ Pas (given, g = 10 m s−2 ).

Q12.Two long straight wires 𝑃 and 𝑄 carrying equal current 10 A each were kept parallel to each other at 5 cm distance. Magnitude of magnetic force experienced by 10 cm length of wire 𝑃 is 𝐹1. If distance between wires is halved and currents on them are doubled, force 𝐹2 on 10 cm length of wire 𝑃 will be: (1) 8𝐹1 (2) 10 𝐹1 𝐹1 𝐹1 (3) (4) 8 10

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.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.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.

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

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.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.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 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

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.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 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.

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 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.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.The electric potential at the centre of two concentric half rings of radii R1 and R2 , having same linear charge density λ is . (1) 2λ (2) λ ∈0 2∈0 (3) λ (4) λ 4∈0 ∈0

Q15.A cubical volume is bounded by the surfaces x = 0, x = a, y = 0, y = a, z = 0, z = a . The electric field in → the region is given by E = E0xˆi. Where E0 = 4 × 104 NC−1 m−1 . If a = 2 cm , the charge contained in the cubical volume is Q × 10–14 C . The value of Q is ______. (Take ϵ0 = 9 × 10−12 C2 N−1m−2 )

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.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.Two parallel plate capacitors C1 and C2 each having capacitance of 10 μF are individually charged by a 100 V D.C. source. Capacitor C1 is kept connected to the source and a dielectric slab is inserted between it plates. Capacitor C2 is disconnected from the source and then a dielectric slab is inserted in it. Afterwards the capacitor C1 is also disconnected from the source and the two capacitors are finally connected in parallel combination. The common potential of the combination will be _____ V . (Assuming Dielectric constant = 10 )

Q16.A thin infinite sheet charge and an infinite line charge of respective charge densities +σ and +λ are placed parallel at 5 m distance from each other. Points P and Q are at π3 m and π4 m perpendicular distances from line charge towards sheet charge, respectively. Ep and Eq are the magnitudes of resultant electric field intensities at point P and Q respectively. If EP = a4 for 2|σ| = |λ|, then the value of a is _____. EQ

Q16.A 600 pF capacitor is charged by 200 V supply. It is then disconnected from the supply and is connected to another uncharged 600 pF capacitor. Electrostatic energy lost in the process is _____ μJ.

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