23 January Morning Shift physics questions with solutions

Showing 1–10 of 24 questions

• MCQmediumRotational Motionangular momentum in pure rotation and its conservation

  Two small balls with masses m and 2m are attached to both ends of a rigid rod of length d and negligible mass. If angular momentum of this system is L about an axis (A) passing through its centre of mass and perpendicular to the rod then angular velocity of the system about A is :

  Options

  • Option A

    3L/(2md²)

  • Option B

    2L/md²

  • Option C

    4L/(3md²)

  • Option D

    2L/(5md²)

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• MCQmediumElectromagnetic wavedisplacement current and properties of electromagnetic wave

  Match List-I with List-II.

  List-I (Relation)

  A. ∮$\vec{E}$·$\vec{dl}$ = -d/dt ∫$\vec{B}$·$\vec{da}$

  B. ∮$\vec{B}$·$\vec{dl}$ = μ₀[I + ε₀ dΦ(E)/dt]

  C. ∮$\vec{E}$·$\vec{da}$ = (1/ε₀)∫ρ dv

  D. ∮$\vec{B}$·$\vec{dl}$= μ₀I

  List-II (Law)

  I. Ampere's circuital law. II. Faraday's laws of electromagnetic induction. III. Ampere-Maxwell law IV. Gauss's law of electrostatics

  Choose the correct answer from the options given below :

  Options

  • Option A

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

  • Option B

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

  • Option C

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

  • Option D

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

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• MCQmediumCurrent electricityequivalent resistance

  A wire of uniform resistance λ Ω/m is bent into a circle of radius r and another piece of wire with length 2r is connected between points A and B (AOB) as shown in figure. The equivalent resistance between points A and B is _____Ω.

  

  Options

  • Option A

    3πλr/8

  • Option B

    (π + 1)2rλ

  • Option C

    6πλr/(3π + 16)

  • Option D

    2πλr

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• MCQmediumAtomic Structure and X-raysatomic structre and bohr atomic model

  In hydrogen atom spectrum, (R → Rydberg's constant)

  A. the maximum wavelength of the radiation of Lyman series is 4/(3R)

  B. the Balmer series lies in the visible region of the spectrum

  C. the minimum wavelength of the radiation of Paschen series is 9/R

  D. the minimum wavelength of Lyman series is 5/(4R)

  Choose the correct answer from the options given below :

  Options

  • Option A

    B, D Only

  • Option B

    A, B and C Only

  • Option C

    A, B and D Only

  • Option D

    A, B Only

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• MCQmediumThermodyanmicsheat and principle of calorimeter

  In a perfectly inelastic collision, two spheres made of the same material with masses 15 kg and 25 kg, moving in opposite directions with speeds of 10 m/s and 30 m/s, respectively, strike each other and stick together. The rise in temperature (in °C), if all the heat produced during the collision is retained by these spheres, is :

  (specific heat of sphere material 31 cal/kg. °C and 1 cal = 4.2 J)

  Options

  • Option A

    1.75

  • Option B

    1.44

  • Option C

    1.15

  • Option D

    1.95

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• NumericeasyAc Cirucuitsseries combination of ac circuit and L-C-R circuit

  Using a variable-frequency a.c. voltage source, the maximum current measured in the given LCR circuit is 50 mA for V=5sin(100t). The values of L and R are shown in the figure. The capacitance of the capacitor (C) used is ________ μF.

  

  Your answer

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• MCQmediumCenter of maas , Momentum and Collisionmomentum and conservation of momentum

  A small both A of mass m is attached to a massless rigid rod of length 1m pivoted at point P and kept at an angle of 60° with vertical as shown in figure. At distance of 1m below point P, an identical bob B is kept at rest on a smooth horizontal surface that extends to a circular track of radius R as shown in figure. If bob B just manages to complete the circular path of radius R upto a point Q after being hit elastically by bob A, then radius R is ______m.

  

  Options

  • Option A

    3/5

  • Option B

    1/5

  • Option C

    (2 + √3)/5

  • Option D

    (2 - √3)/5

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• MCQmediumElectromagnetic Inductionmotional emf and induced emf in rotating rod

  A 20 m long uniform copper wire held horizontally is allowed to fall under the gravity (g = 10 m/s²) through a uniform horizontal magnetic field of 0.5 Gauss perpendicular to the length of the wire. The induced EMF across the wire it travells a vertical distance of 200 m is _____ mV.

  Options

  • Option A

    0.2√10

  • Option B

    20√10

  • Option C

    2√10

  • Option D

    200√10

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• MCQmediumWork , Power and EnergySpring Energy and Conservation of Energy

  Two blocks with masses 100g and 200g are attached to the ends of springs A and B as shown in figure. The energy stored in A is E. The energy stored in B, when spring constants $k_{A}$, $k_{B}$ of A and B, respectively satisfy the relation 4$k_{A}$= 3$k_{B}$, is :

  

  Options

  • Option A

    4E

  • Option B

    2E

  • Option C

    3E

  • Option D

    4E/3

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• MCQeasyWork , Power and Energykinetic enegy and work engery theorem

  An object is projected with kinetic energy K from a point A at an angle 60° with the horizontal. The ratio of the difference in kinetic energies points B and C to that at point A (see figure), in the absence of air friction is :

  

  Options

  • Option A

    1 : 2

  • Option B

    2 : 3

  • Option C

    1 : 4

  • Option D

    3 : 4

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