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JEE Main 2024 Jan 30 Shift 2Physics

30 questions · 30 with the official NTA answer

Q31JEE Main 2024 Jan 30 Shift 2Units and MeasurementsMedium

If mass is written as m=kcPG1/2h1/2m = k\, c^{P}\, G^{-1/2}\, h^{1/2} then the value of PP will be : (Constants have their usual meaning with kk a dimensionless constant)

  1. A

    1/31/3

  2. B

    22

  3. C

    1/3-1/3

  4. D

    1/21/2

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Correct option: D

Q32JEE Main 2024 Jan 30 Shift 2KinematicsMedium

Projectiles A and B are thrown at angles of 45°45° and 60°60° with vertical respectively from top of a 400400 m high tower. If their ranges and times of flight are same, the ratio of their speeds of projection vA:vBv_{\mathrm{A}} : v_{\mathrm{B}} is :

[Take g=10 ms2g = 10\ ms^{-2}]

  1. A

    1:21:2

  2. B

    1:21:\sqrt{2}

  3. C

    2:1\sqrt{2}:1

  4. D

    1:31:\sqrt{3}

Show answer

Correct option: B

Q33JEE Main 2024 Jan 30 Shift 2Laws of MotionEasy

Three blocks AA, BB and CC are pulled on a horizontal smooth surface by a force of 80N80N as shown in figure

Figure — described from the original paper

blocks A (5 kg), B (3 kg) and C (2 kg) in a row connected by strings with tensions T1T_1 (between A and B) and T2T_2 (between B and C); force F=80NF = 80N applied to C towards the right

The tensions T1T_1 and T2T_2 in the string are respectively:

  1. A

    40N, 64N40N,\ 64N

  2. B

    60N, 80N60N,\ 80N

  3. C

    88N, 96N88N,\ 96N

  4. D

    80N, 100N80N,\ 100N

Show answer

Correct option: A

Q34JEE Main 2024 Jan 30 Shift 2Laws of MotionHard

A block of mass mm is placed on a surface having vertical crossection given by y=x2/4y = x^2/4. If coefficient of friction is 0.50.5, the maximum height above the ground at which block can be placed without slipping is:

  1. A

    1/4 m1/4\ m

  2. B

    1/6 m1/6\ m

  3. C

    1/2 m1/2\ m

  4. D

    1/3 m1/3\ m

Show answer

Correct option: A

Q35JEE Main 2024 Jan 30 Shift 2Work, Energy and PowerMedium

A block of mass 11 kg is pushed up a surface inclined to horizontal at an angle of 60°60° by a force of 10 N10\ N parallel to the inclined surface as shown in figure. When the block is pushed up by 10 m10\ m along inclined surface, the work done against frictional force is :

[g=10 m/s2g = 10\ m/s^2]

Figure — described from the original paper

incline at 60°60° to the horizontal with block MM on it, coefficient of static friction μs=0.1\mu_s = 0.1, force of 10 N10\ N applied up along the incline

  1. A

    53 J5\sqrt{3}\ J

  2. B

    5 J5\ J

  3. C

    5×103 J5 \times 10^3\ J

  4. D

    10 J10\ J

Show answer

Correct option: B

Q36JEE Main 2024 Jan 30 Shift 2GravitationEasy

Escape velocity of a body from earth is 11.2 km/s11.2\ km/s. If the radius of a planet be one-third the radius of earth and mass be one-sixth that of earth, the escape velocity from the planet is :

  1. A

    4.2 km/s4.2\ km/s

  2. B

    7.9 km/s7.9\ km/s

  3. C

    8.4 km/s8.4\ km/s

  4. D

    11.2 km/s11.2\ km/s

Show answer

Correct option: B

Q37JEE Main 2024 Jan 30 Shift 2Properties of Solids and LiquidsMedium

A block of ice at 10°C-10°C is slowly heated and converted to steam at 100°C100°C. Which of the following curves represent the phenomenon qualitatively:

  1. A
    Figure — described from the original paper

    Temperature vs Heat supplied graph — temperature rises linearly from the origin, stays constant (plateau), rises again, then stays constant at the top

  2. B
    Figure — described from the original paper

    Temperature vs Heat supplied graph — temperature starts from a point on the heat-supplied axis (right of origin), rises linearly, stays constant (plateau), then rises again at the end

  3. C
    Figure — described from the original paper

    Temperature vs Heat supplied graph — temperature jumps up sharply near the origin, stays constant (plateau), then rises linearly

  4. D
    Figure — described from the original paper

    Temperature vs Heat supplied graph — temperature starts from a point on the heat-supplied axis, rises, stays constant, jumps vertically up, stays constant again, then rises at the end

Show answer

Correct option: A

Q38JEE Main 2024 Jan 30 Shift 2ThermodynamicsMedium

Choose the correct statement for processes AA & BB shown in figure.

Figure — described from the original paper

P–V diagram with two downward-sloping curves; curve A is lower and less steep, curve B is higher and steeper, both with arrows directed toward increasing V

  1. A

    PV=kPV = k for process BB and AA.

  2. B

    PVγ=kPV^{\gamma} = k for process BB and PV=kPV = k for process AA.

  3. C

    Pγ1Tγ=k\dfrac{P^{\gamma-1}}{T^{\gamma}} = k for process BB and T=kT = k for process AA.

  4. D

    TγPγ1=k\dfrac{T^{\gamma}}{P^{\gamma-1}} = k for process AA and PV=kPV = k for process BB.

Show answer

Correct option: B

Q39JEE Main 2024 Jan 30 Shift 2Kinetic Theory of GasesMedium

If three moles of monoatomic gas (γ=53)\left(\gamma = \frac{5}{3}\right) is mixed with two moles of a diatomic gas (γ=75)\left(\gamma = \frac{7}{5}\right), the value of adiabatic exponent γ\gamma for the mixture is

  1. A

    1.401.40

  2. B

    1.521.52

  3. C

    1.751.75

  4. D

    1.351.35

Show answer

Correct option: B

Q40JEE Main 2024 Jan 30 Shift 2ElectrostaticsMedium

A particle of charge 'q-q' and mass 'mm' moves in a circle of radius 'rr' around an infinitely long line charge of linear charge density '+λ+\lambda'. Then time period will be given as :

(Consider kk as Coulomb's constant)

  1. A

    T=2πrm2kλqT = 2\pi r \sqrt{\dfrac{m}{2k\lambda q}}

  2. B

    T2=4π2m2kλqr3T^2 = \dfrac{4\pi^2 m}{2k\lambda q} r^3

  3. C

    T=12π2kλqmT = \dfrac{1}{2\pi} \sqrt{\dfrac{2k\lambda q}{m}}

  4. D

    T=12πrm2kλqT = \dfrac{1}{2\pi r} \sqrt{\dfrac{m}{2k\lambda q}}

Show answer

Correct option: A

Q41JEE Main 2024 Jan 30 Shift 2Current ElectricityEasy

When a potential difference VV is applied across a wire of resistance RR, it dissipates energy at a rate WW. If the wire is cut into two halves and these halves are connected mutually parallel across the same supply, the energy dissipation rate will become:

  1. A

    2W2W

  2. B

    1/2W1/2W

  3. C

    4W4W

  4. D

    1/4W1/4W

Show answer

Correct option: C

Q42JEE Main 2024 Jan 30 Shift 2Electromagnetic WavesEasy

Match List I with List II

List I List II
A. Gauss's law of magnetostatics I. Eda=1εoρdV\oint \vec{E} \cdot \vec{da} = \dfrac{1}{\varepsilon_o} \int \rho \, dV
B. Faraday's law of electro magnetic induction II. Bda=0\oint \vec{B} \cdot \vec{da} = 0
C. Ampere's law III. Edl=ddtBda\int \vec{E} \cdot \vec{dl} = \dfrac{-d}{dt} \int \vec{B} \cdot \vec{da}
D. Gauss's law of electrostatics IV. Bdl=μ0I\oint \vec{B} \cdot \vec{dl} = \mu_0 I

Choose the correct answer from the options given below:

  1. A

    A-IV, B-II, C-III, D-I

  2. B

    A-II, B-III, C-IV, D-I

  3. C

    A-I, B-III, C-IV, D-II

  4. D

    A-III, B-IV, C-I, D-II

Show answer

Correct option: B

Q43JEE Main 2024 Jan 30 Shift 2Electromagnetic Induction and Alternating CurrentsMedium

An alternating voltage V(t)=220sin100πtV(t) = 220 \sin 100\pi t volt is applied to a purely resistive load of 50 Ω50\ \Omega. The time taken for the current to rise from half of the peak value to the peak value is:

  1. A

    3.3 ms3.3\ ms

  2. B

    2.2 ms2.2\ ms

  3. C

    7.2 ms7.2\ ms

  4. D

    5 ms5\ ms

Show answer

Correct option: A

Q44JEE Main 2024 Jan 30 Shift 2Electromagnetic WavesMedium

If the total energy transferred to a surface in time tt is 6.48×105 J6.48 \times 10^5\ J, then the magnitude of the total momentum delivered to this surface for complete absorption will be:

  1. A

    2.16×103 kg m/s2.16 \times 10^{-3}\ kg\ m/s

  2. B

    4.32×103 kg m/s4.32 \times 10^{-3}\ kg\ m/s

  3. C

    1.58×103 kg m/s1.58 \times 10^{-3}\ kg\ m/s

  4. D

    2.46×103 kg m/s2.46 \times 10^{-3}\ kg\ m/s

Show answer

Correct option: A

Q45JEE Main 2024 Jan 30 Shift 2Wave OpticsEasy

A beam of unpolarised light of intensity IoI_o is passed through a polaroid AA and then through another polaroid BB which is oriented so that its principal plane makes an angle of 45°45° relative to that of AA. The intensity of emergent light is:

  1. A

    IoI_o

  2. B

    Io/2I_o/2

  3. C

    Io/4I_o/4

  4. D

    Io/8I_o/8

Show answer

Correct option: C

Q46JEE Main 2024 Jan 30 Shift 2Dual Nature of Matter and RadiationEasy

For the photoelectric effect, the maximum kinetic energy (Ek)(E_k) of the photoelectrons is plotted against the frequency (ν)(\nu) of the incident photons as shown in figure. The slope of the graph gives

Figure — described from the original paper

straight-line graph of EkE_k (y-axis) versus ν\nu (x-axis), intersecting the ν\nu-axis at a positive intercept and making angle θ\theta with it

  1. A

    Planck's constant

  2. B

    Charge of electron

  3. C

    Work function of the metal

  4. D

    Ratio of Planck's constant to electric charge

Show answer

Correct option: A

Q47JEE Main 2024 Jan 30 Shift 2Atoms and NucleiMedium

In a nuclear fission reaction of an isotope of mass MM, three similar daughter nuclei of same mass are formed. The speed of a daughter nuclei in terms of mass defect ΔM\Delta M will be :

  1. A

    ΔMc23\dfrac{\Delta M c^2}{3}

  2. B

    c2ΔMMc\sqrt{\dfrac{2\Delta M}{M}}

  3. C

    c3ΔMMc\sqrt{\dfrac{3\Delta M}{M}}

  4. D

    2cΔMM\sqrt{\dfrac{2c\Delta M}{M}}

Show answer

Correct option: B

Q48JEE Main 2024 Jan 30 Shift 2Atoms and NucleiEasy

An electron revolving in nthn^{\text{th}} Bohr orbit has magnetic moment μn\mu_n. If μnnx\mu_n \propto n^x, the value of xx is

  1. A

    00

  2. B

    11

  3. C

    22

  4. D

    33

Show answer

Correct option: B

Q49JEE Main 2024 Jan 30 Shift 2Electronic DevicesMedium
Figure — described from the original paper

series circuit with a 15 V battery, diode D1D_1 (Ge) and diode D2D_2 (Si) both forward biased, a 1.5 kΩ1.5\ k\Omega resistor, and a load resistance RL=2.5 kΩR_L = 2.5\ k\Omega across which the voltage is measured

In the given circuit, the voltage across load resistance (RL)(R_L) is:

  1. A

    8.50 V8.50\ V

  2. B

    8.75 V8.75\ V

  3. C

    9.00 V9.00\ V

  4. D

    14.00 V14.00\ V

Show answer

Correct option: B

Q50JEE Main 2024 Jan 30 Shift 2Experimental SkillsEasy

If 5050 Vernier divisions are equal to 4949 main scale divisions of a traveling microscope and one smallest reading of main scale is 0.5 mm0.5\ mm, the Vernier constant of traveling microscope is

  1. A

    0.1 mm0.1\ mm

  2. B

    0.01 cm0.01\ cm

  3. C

    0.01 mm0.01\ mm

  4. D

    0.1 cm0.1\ cm

Show answer

Correct option: C

Q51JEE Main 2024 Jan 30 Shift 2KinematicsEasyNumerical

A vector has magnitude same as that of A=3i^+4j^\vec{A} = 3\hat{i} + 4\hat{j} and is parallel to B=4i^+3j^\vec{B} = 4\hat{i} + 3\hat{j}. The xx and yy components of this vector in first quadrant are xx and 33 respectively where x=x = ________.

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Answer: 4

Q52JEE Main 2024 Jan 30 Shift 2Rotational MotionMediumNumerical

Two discs of moment of inertia I1=4 kg m2I_1 = 4\ kg\ m^2 and I2=2 kg m2I_2 = 2\ kg\ m^2, about their central axes & normal to their planes, rotating with angular speeds 10 rad/s10\ rad/s & 4 rad/s4\ rad/s respectively are brought into contact face to face with their axes of rotation coincident. The loss in kinetic energy of the system in the process is ________ J.

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Answer: 24

Q53JEE Main 2024 Jan 30 Shift 2Properties of Solids and LiquidsMediumNumerical

A big drop is formed by coalescing 10001000 small identical drops of water. If E1E_1 be the total surface energy of 10001000 small drops of water and E2E_2 be the surface energy of single big drop of water, then E1:E2E_1 : E_2 is x:1x : 1 where x=x = _______.

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Answer: 10

Q54JEE Main 2024 Jan 30 Shift 2WavesMediumNumerical

A point source is emitting sound waves of intensity 16×108 Wm216 \times 10^{-8}\ Wm^{-2} at the origin. The difference in intensity (magnitude only) at two points located at a distances of 2m2m and 4m4m from the origin respectively will be _______ × 108 Wm2\times\ 10^{-8}\ Wm^{-2}.

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Answer: 3

Q55JEE Main 2024 Jan 30 Shift 2ElectrostaticsHardNumerical

Two identical charged spheres are suspended by strings of equal lengths. The strings make an angle of 37°37° with each other. When suspended in a liquid of density 0.7 g/cm30.7\ g/cm^3, the angle remains same. If density of material of the sphere is 1.4 g/cm31.4\ g/cm^3, the dielectric constant of the liquid is _______ (tan37°=34)\left(\tan 37° = \frac{3}{4}\right)

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Answer: 2

Q56JEE Main 2024 Jan 30 Shift 2Current ElectricityMediumNumerical

Two resistance of 100 Ω100\ \Omega and 200 Ω200\ \Omega are connected in series with a battery of 4 V4\ V and negligible internal resistance . A voltmeter is used to measure voltage across 100 Ω100\ \Omega resistance, which gives reading as 1 V1\ V. The resistance of voltmeter must be _______ Ω\Omega.

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Answer: 200

Q57JEE Main 2024 Jan 30 Shift 2Magnetic Effects of Current and MagnetismMediumNumerical

The current of 5A5A flows in a square loop of sides 1 m1\ m is placed in air. The magnetic field at the centre of the loop is X2×107 TX\sqrt{2} \times 10^{-7}\ T. The value of XX is ________.

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Answer: 40

Q58JEE Main 2024 Jan 30 Shift 2Electromagnetic Induction and Alternating CurrentsMediumNumerical

A power transmission line feeds input power at 2.3 kV2.3\ kV to a step down transformer with its primary winding having 30003000 turns. The output power is delivered at 230 V230\ V by the transformer. The current in the primary of the transformer is 5A5A and its efficiency is 90%90\%. The winding of transformer is made of copper. The output current of transformer is _______ AA.

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Answer: 45

Q59JEE Main 2024 Jan 30 Shift 2Experimental SkillsMediumNumerical

In an experiment to measure the focal length (f)(f) of a convex lens, the magnitude of object distance (x)(x) and the image distance (y)(y) are measured with reference to the focal point of the lens. The yy-xx plot is shown in figure.

The focal length of the lens is ________ cmcm.

Figure — described from the original paper

y–x graph with y (cm) and x (cm) axes marked 10 to 40; data points A, B, C, D, E lie on a downward-sloping curve/line, with point C near (20, 20)

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Answer: 20

Q60JEE Main 2024 Jan 30 Shift 2OscillationsMediumNumerical

A simple pendulum is placed at a place where its distance from the earth's surface is equal to the radius of the earth. If the length of the string is 4m4m, then the time period of small oscillations will be _______ ss. [take g=π2 ms2g = \pi^2\ ms^{-2}]

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Answer: 8