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JEE Main 2024 Feb 1 Shift 1Physics

30 questions · 29 with the official NTA answer

Q31JEE Main 2024 Feb 1 Shift 1Units and MeasurementsEasy

The dimensional formula of angular impulse is :

  1. A

    [ML2T2][\mathrm{M\,L^2\,T^{-2}}]

  2. B

    [MLT1][\mathrm{M\,L\,T^{-1}}]

  3. C

    [ML2T1][\mathrm{M\,L^{-2}\,T^{-1}}]

  4. D

    [ML2T1][\mathrm{M\,L^2\,T^{-1}}]

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Correct option: D

Q32JEE Main 2024 Feb 1 Shift 1KinematicsMedium

A particle moving in a circle of radius R with uniform speed takes time T to complete one revolution. If this particle is projected with the same speed at an angle θ\theta to the horizontal, the maximum height attained by it is equal to 4R. The angle of projection θ\theta is then given by :

  1. A

    cos1[2gT2π2R]12\cos^{-1}\left[\dfrac{2gT^2}{\pi^2 R}\right]^{\frac{1}{2}}

  2. B

    sin1[2gT2π2R]12\sin^{-1}\left[\dfrac{2gT^2}{\pi^2 R}\right]^{\frac{1}{2}}

  3. C

    sin1[π2R2gT2]12\sin^{-1}\left[\dfrac{\pi^2 R}{2gT^2}\right]^{\frac{1}{2}}

  4. D

    cos1[πR2gT2]12\cos^{-1}\left[\dfrac{\pi R}{2gT^2}\right]^{\frac{1}{2}}

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Correct option: B

Q33JEE Main 2024 Feb 1 Shift 1Laws of MotionMedium

Consider a block and trolley system as shown in figure. If the coefficient of kinetic friction between the trolley and the surface is 0.04, the acceleration of the system in ms2\mathrm{ms^{-2}} is :

(Consider that the string is massless and unstretchable and the pulley is also massless and frictionless) :

Figure — described from the original paper

a 20 kg trolley on a horizontal surface (kinetic friction fkf_k acting on it) connected by a string over a pulley at the table edge to a hanging 6 kg block with a 60 N downward force marked

  1. A

    3

  2. B

    1.2

  3. C

    4

  4. D

    2

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Correct option: D

Q34JEE Main 2024 Feb 1 Shift 1Laws of MotionEasy

A ball of mass 0.5 kg is attached to a string of length 50 cm. The ball is rotated on a horizontal circular path about its vertical axis. The maximum tension that the string can bear is 400 N. The maximum possible value of angular velocity of the ball in rad/s is, :

  1. A

    1600

  2. B

    40

  3. C

    20

  4. D

    10

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Correct option: B

Q35JEE Main 2024 Feb 1 Shift 1Work, Energy and PowerMedium

A simple pendulum of length 1 m has a wooden bob of mass 1 kg. It is struck by a bullet of mass 10210^{-2} kg moving with a speed of 2×102 ms12 \times 10^{2}\ \mathrm{ms^{-1}}. The bullet gets embedded into the bob. The height to which the bob rises before swinging back is. (use g=10 m/s2g = 10\ \mathrm{m/s^2})

  1. A

    0.20 m

  2. B

    0.30 m

  3. C

    0.35 m

  4. D

    0.40 m

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Correct option: A

Q36JEE Main 2024 Feb 1 Shift 1OscillationsMedium

If R is the radius of the earth and the acceleration due to gravity on the surface of earth is g=π2 m/s2g = \pi^2\ \mathrm{m/s^2}, then the length of the second's pendulum at a height h = 2R from the surface of earth will be, :

  1. A

    29\dfrac{2}{9} m

  2. B

    49\dfrac{4}{9} m

  3. C

    89\dfrac{8}{9} m

  4. D

    19\dfrac{1}{9} m

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Correct option: D

Q37JEE Main 2024 Feb 1 Shift 1Properties of Solids and LiquidsEasy

With rise in temperature, the Young's modulus of elasticity :

  1. A

    decreases

  2. B

    increases

  3. C

    remains unchanged

  4. D

    changes erratically

Q38JEE Main 2024 Feb 1 Shift 1ThermodynamicsMedium

The pressure and volume of an ideal gas are related as PV32=KPV^{\frac{3}{2}} = K (Constant). The work done when the gas is taken from state A (P1,V1,T1)(P_1, V_1, T_1) to state B (P2,V2,T2)(P_2, V_2, T_2) is :

  1. A

    2(P2V2P1V1)2\,(P_2 V_2 - P_1 V_1)

  2. B

    2(P2V2P1V1)2\left(P_2\sqrt{V_2} - P_1\sqrt{V_1}\right)

  3. C

    2(P1V1P2V2)2\,(P_1 V_1 - P_2 V_2)

  4. D

    2(P1V1P2V2)2\left(\sqrt{P_1}\,V_1 - \sqrt{P_2}\,V_2\right)

Show answer

Correct option: C

Q39JEE Main 2024 Feb 1 Shift 1Kinetic Theory of GasesMedium

Two moles a monoatomic gas is mixed with six moles of a diatomic gas. The molar specific heat of the mixture at constant volume is :

  1. A

    52R\dfrac{5}{2}R

  2. B

    94R\dfrac{9}{4}R

  3. C

    32R\dfrac{3}{2}R

  4. D

    74R\dfrac{7}{4}R

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Correct option: B

Q40JEE Main 2024 Feb 1 Shift 1ElectrostaticsMedium

Two identical capacitors have same capacitance C. One of them is charged to the potential V and other to the potential 2V. The negative ends of both are connected together. When the positive ends are also joined together, the decrease in energy of the combined system is :

  1. A

    12CV2\dfrac{1}{2}CV^2

  2. B

    14CV2\dfrac{1}{4}CV^2

  3. C

    2CV22\,CV^2

  4. D

    34CV2\dfrac{3}{4}CV^2

Show answer

Correct option: B

Q41JEE Main 2024 Feb 1 Shift 1Current ElectricityMedium

The reading in the ideal voltmeter (V) shown in the given circuit diagram is :

Figure — described from the original paper

a closed loop containing, in the top branch, three cells of 5V each with internal resistance 0.2 Ω each; in the left branch one 5V cell with 0.2 Ω; in the bottom branch three 5V cells with 0.2 Ω each; on the right, a 5V cell with 0.2 Ω connected across an ideal voltmeter (V)

  1. A

    5V

  2. B

    3V

  3. C

    0V

  4. D

    10V

Show answer

Correct option: C

Q42JEE Main 2024 Feb 1 Shift 1Magnetic Effects of Current and MagnetismEasy

A galvanometer has a resistance of 50 Ω\Omega and it allows maximum current of 5 mA. It can be converted into voltmeter to measure upto 100 V by connecting in series a resistor of resistance :

  1. A

    19950 Ω\Omega

  2. B

    19500 Ω\Omega

  3. C

    5975 Ω\Omega

  4. D

    20050 Ω\Omega

Show answer

Correct option: A

Q43JEE Main 2024 Feb 1 Shift 1Electromagnetic Induction and Alternating CurrentsEasy

In series LCR circuit, the capacitance is changed from C to 4C. To keep the resonance frequency unchanged, the new inductance should be :

  1. A

    increased to 4L

  2. B

    increased by 2L

  3. C

    reduced by 14\dfrac{1}{4}L

  4. D

    reduced by 34\dfrac{3}{4}L

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Correct option: D

Q44JEE Main 2024 Feb 1 Shift 1Electromagnetic WavesMedium

A parallel plate capacitor has a capacitance C = 200 pF. It is connected to 230 V ac supply with an angular frequency 300 rad/s. The rms value of conduction current in the circuit and displacement current in the capacitor respectively are :

  1. A

    13.8 μ\muA and 13.8 μ\muA

  2. B

    1.38 μ\muA and 1.38 μ\muA

  3. C

    14.3 μ\muA and 143 μ\muA

  4. D

    13.8 μ\muA and 138 μ\muA

Show answer

Correct option: A

Q45JEE Main 2024 Feb 1 Shift 1Wave OpticsMedium

A monochromatic light of wavelength 6000A˚\text{Å} is incident on the single slit of width 0.01 mm. If the diffraction pattern is formed at the focus of the convex lens of focal length 20 cm, the linear width of the central maximum is :

  1. A

    12 mm

  2. B

    24 mm

  3. C

    120 mm

  4. D

    60 mm

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Correct option: B

Q46JEE Main 2024 Feb 1 Shift 1Dual Nature of Matter and RadiationMedium

The de Broglie wavelengths of a proton and an α\alpha particle are λ\lambda and 2λ2\lambda respectively. The ratio of the velocities of proton and α\alpha particle will be :

  1. A

    1 : 8

  2. B

    4 : 1

  3. C

    8 : 1

  4. D

    1 : 2

Show answer

Correct option: C

Q47JEE Main 2024 Feb 1 Shift 1Atoms and NucleiMedium

The minimum energy required by a hydrogen atom in ground state to emit radiation in Balmer series is nearly :

  1. A

    13.6 eV

  2. B

    1.5 eV

  3. C

    12.1 eV

  4. D

    1.9 eV

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Correct option: C

Q48JEE Main 2024 Feb 1 Shift 1Electronic DevicesMedium

In the given circuit if the power rating of Zener diode is 10 mW, the value of series resistance RsR_s to regulate the input unregulated supply is :

Figure — described from the original paper

an unregulated supply Vs=8VV_s = 8\,\mathrm{V} in series with resistor RsR_s, feeding a Zener diode (Vz=5VV_z = 5\,\mathrm{V}) in parallel with a load resistor RL=1kΩR_L = 1\,\mathrm{k\Omega}

  1. A

    10 kΩ\Omega

  2. B

    1 kΩ\Omega

  3. C

    10 Ω\Omega

  4. D

    5 kΩ\Omega

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Correct option: B

Q49JEE Main 2024 Feb 1 Shift 1Experimental SkillsMedium

10 divisions on the main scale of a Vernier calliper coincide with 11 divisions on the Vernier scale. If each division on the main scale is of 5 units, the least count of the instrument is :

  1. A

    12\dfrac{1}{2}

  2. B

    511\dfrac{5}{11}

  3. C

    1011\dfrac{10}{11}

  4. D

    5011\dfrac{50}{11}

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Correct option: B

Q50JEE Main 2024 Feb 1 Shift 1Units and MeasurementsMedium

The radius (r), length (ll) and resistance (R) of a metal wire was measured in the laboratory as

r=(0.35±0.05)r = (0.35 \pm 0.05) cm

R=(100±10)R = (100 \pm 10) ohm

l=(15±0.2)l = (15 \pm 0.2) cm

The percentage error in resistivity of the material of the wire is :

  1. A

    39.9%

  2. B

    25.6%

  3. C

    37.3%

  4. D

    35.6%

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Correct option: A

Q51JEE Main 2024 Feb 1 Shift 1KinematicsMediumNumerical

A particle is moving in one dimension (along xx axis) under the action of a variable force. It's initial position was 16 m right of origin. The variation of its position (xx) with time (t) is given as x=3t3+18t2+16tx = -3t^3 + 18t^2 + 16t, where xx is in m and t is in s. The velocity of the particle when its acceleration becomes zero is ________ m/s.

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Answer: 52

Q52JEE Main 2024 Feb 1 Shift 1Rotational MotionMediumNumerical

The identical spheres each of mass 2M are placed at the corners of a right angled triangle with mutually perpendicular sides equal to 4 m each. Taking point of intersection of these two sides as origin, the magnitude of position vector of the centre of mass of the system is 42x\dfrac{4\sqrt{2}}{x}, where the value of xx is ________

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Answer: 3

Q53JEE Main 2024 Feb 1 Shift 1Properties of Solids and LiquidsMediumNumerical

A plane is in level flight at constant speed and each of its two wings has an area of 40 m2\mathrm{m^2}. If the speed of the air is 180 km/h over the lower wing surface and 252 km/h over the upper wing surface, the mass of the plane is ________ kg. (Take air density to be 1 kg m3\mathrm{kg\ m^{-3}} and g=10 ms2g = 10\ \mathrm{ms^{-2}})

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Answer: 9600

Q54JEE Main 2024 Feb 1 Shift 1WavesMediumNumerical

A tuning fork resonates with a sonometer wire of length 1 m stretched with a tension of 6 N. When the tension in the wire is changed to 54 N, the same tuning fork produces 12 beats per second with it. The frequency of the tuning fork is ________ Hz.

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Answer: 6

Q55JEE Main 2024 Feb 1 Shift 1ElectrostaticsMediumNumerical

Two identical charged spheres are suspended by strings of equal lengths. The strings make an angle θ\theta 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)

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Answer: 3

Q56JEE Main 2024 Feb 1 Shift 1Current ElectricityEasyNumerical

The current in a conductor is expressed as I=3t2+4t3I = 3t^2 + 4t^3, where I is in Ampere and t is in second. The amount of electric charge that flows through a section of the conductor during t = 1s to t = 2s is ________ C.

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Answer: 22

Q57JEE Main 2024 Feb 1 Shift 1Magnetic Effects of Current and MagnetismMediumNumerical

A regular polygon of 6 sides is formed by bending a wire of length 4π4\pi meter. If an electric current of 4π34\pi\sqrt{3} A is flowing through the sides of the polygon, the magnetic field at the centre of the polygon would be x×107x \times 10^{-7} T. The value of xx is ________.

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Answer: 72

Q58JEE Main 2024 Feb 1 Shift 1Electromagnetic Induction and Alternating CurrentsHardNumerical

A rectangular loop of sides 12 cm and 5 cm, with its sides parallel to the xx-axis and yy-axis respectively, moves with a velocity of 5 cm/s in the positive xx axis direction, in a space containing a variable magnetic field in the positive zz direction. The field has a gradient of 10310^{-3} T/cm along the negative xx direction and it is decreasing with time at the rate of 10310^{-3} T/s. If the resistance of the loop is 6 mΩ\Omega, the power dissipated by the loop as heat is ________ ×109\times 10^{-9} W.

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Answer: 216

Q59JEE Main 2024 Feb 1 Shift 1Ray OpticsMediumNumerical

The distance between object and its 3 times magnified virtual image as produced by a convex lens is 20 cm. The focal length of the lens used is ________ cm.

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Answer: 15

Q60JEE Main 2024 Feb 1 Shift 1Atoms and NucleiMediumNumerical

The radius of a nucleus of mass number 64 is 4.8 fermi. Then the mass number of another nucleus having radius of 4 fermi is 1000x\dfrac{1000}{x}, where xx is ________.

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Answer: 27