31 January 2023 physics questions with solutions

Showing 1–10 of 57 questions

• NumericmediumAtomic Structure and X-raysatomic structure and bohr atomic model

  For hydrogen atom, λ₁ and λ₂ are the wavelengths corresponding to transitions 1 and 2 shown in the figure. The ratio λ₁/λ₂ is x/32. The value of x is ______.

  

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  JEE Mains31 January 2023Shift 1Morning Shift

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• MCQeasyWave Motionsound wave and its general equation and velocity

  For a solid rod, Young's modulus is 3.2 × 10¹¹ N m⁻² and density is 8 × 10³ kg m⁻³. The velocity of longitudinal wave in the rod will be:

  Options

  • Option A

    145.75 × 10³ m s⁻¹

  • Option B

    3.65 × 10³ m s⁻¹

  • Option C

    18.96 × 10³ m s⁻¹

  • Option D

    6.32 × 10³ m s⁻¹

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  JEE Mains31 January 2023Shift 2Evening Shift

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• MatcheasyElectromagnetic wavedisplacement current and properties of electromagnetic wave

  Match List-I with List-II:

  List 1

  1. A. Microwaves

  2. B. UV rays

  3. C. Infra-red rays

  4. D. X-rays

  List 2

  1. I. Physiotherapy

  2. II. Treatment of cancer

  3. III. LASIK eye surgery

  4. IV. Aircraft navigation

  Options

  • Option A

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

  • Option B

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

  • Option C

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

  • Option D

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

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  JEE Mains31 January 2023Shift 2Evening Shift

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• MCQeasyRotational Motioncombined translatory and rotatory motion ,Pure rolling motion

  As shown in figure, a 70 kg garden roller is pushed with a force F = 200 N at an angle of 30° with horizontal. The normal reaction on the roller is: [g = 10 m s⁻²]

  

  Options

  • Option A

    800√2 N

  • Option B

    600 N

  • Option C

    800 N

  • Option D

    200√3 N

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  JEE Mains31 January 2023Shift 1Morning Shift

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• MCQeasyThermodynamicsthermodynmic process and work done

  The correct relation between γ = $C_{p}$/$C_{v}$and temperature T is:

  Options

  • Option A

    γ ∝ 1/√T

  • Option B

    γ ∝ T⁰

  • Option C

    γ ∝ 1/T

  • Option D

    γ ∝ T

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• NumericmediumRotational Motioncombined translatory and rotatory motion ,Pure rolling motion

  A solid sphere of mass 1 kg rolls without slipping on a plane surface. Its kinetic energy is 7 × 10⁻³ J. The speed of the centre of mass of the sphere is ______ cm s⁻¹.

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  JEE Mains31 January 2023Shift 1Morning Shift

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• MCQmediumMagnetic effect of currentmagnetic moment and torque on current carring loop in magnetic field

  The number of turns of the coil of a moving coil galvanometer is increased in order to increase current sensitivity by 50%. The percentage change in voltage sensitivity of the galvanometer will be:

  Options

  • Option A

    100%

  • Option B

    50%

  • Option C

    75%

  • Option D

    0%

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  JEE Mains31 January 2023Shift 2Evening Shift

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• MCQeasysemiconductorP-N jucntion and diode in reverse and forward bias

  The effect of increase in temperature on the number of electrons in conduction band $n_{e}$ and resistance of a semiconductor will be as:

  Options

  • Option A

    Both $n_{e}$ and resistance decrease

  • Option B

    Both $n_{e}$ and resistance increase

  • Option C

    $n_{e}$ increases, resistance decreases

  • Option D

    $n_{e}$ decreases, resistance increases

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• MCQmediumThermodynamicsfirst law of thermodynamics

  Heat energy of 735 J is given to a diatomic gas allowing the gas to expand at constant pressure. Each gas molecule rotates around an internal axis but does not oscillate. The increase in internal energy of the gas will be:

  Options

  • Option A

    525 J

  • Option B

    441 J

  • Option C

    572 J

  • Option D

    735 J

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  JEE Mains31 January 2023Shift 2Evening Shift

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• MCQeasyAtomic Structure and X-raysatomic structure and bohr atomic model

  The radius of electron's second stationary orbit in Bohr's atom is R. The radius of 3rd orbit will be:

  Options

  • Option A

    R/3

  • Option B

    2.25R

  • Option C

    3R

  • Option D

    9R

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