PYQ Vault

Day 352: JEE Mains Physics

5 questions. Try each one first, then open its answer.

  1. Question 1

    Alternating Current. Asked once: 2021 Paper 25 (same type asked 5 times) See all 5 of this type

    25
    In a series LCR resonant circuit, the quality factor is measured as 100. If the inductance is increased by two- fold and resistance is decreased by two -fold, then the quality factor after this change will be ____\_\_\_\_.
  2. Question 2

    Nuclei. Asked once: 2021 Paper 15 (same type asked 5 times) See all 5 of this type

    11
    A radioactive nucleus decays so that after 30 years, only 18th \frac{1}{8}^{\text{th~}} of the initial sample is active. What is the half-life of sample?

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  3. Question 3

    Kinetic Theory. Asked once: 28 Jul 2022 (same type asked 5 times) See all 5 of this type

    8
    Given below are two statements: Statement I: The average momentum of a molecule in a sample of an ideal gas depends on temperature. Statement II: The rms speed of oxygen molecules in a gas is vv. If the temperature is doubled and the oxygen molecules dissociate into oxygen atoms, the rms speed will become 2v2v. In the light of the above statements, choose the correct answer from the options given below:

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  4. Question 4

    Oscillations. Asked once: 2021 Paper 4 (same type asked 5 times) See all 5 of this type

    3
    Two identical spring of spring constant ' 2 K2\text{ }K ' are attached to a block of mass mm and to fixed support (see figure). When the mass is displaced from equilibrium position on either side, it executes simple harmonic motion. Then time period of oscillations of this system is:

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  5. Question 5

    Alternating Current. Asked once: 14 Jun 2022 (same type asked 5 times) See all 5 of this type

    24
    As shown in the figure an inductor of inductance 200mH200mH is connected to an AC source of emf 220 V220\text{ }V and frequency 50 Hz50\text{ }Hz. The instantaneous voltage of the source is 0 V0\text{ }V when the peak value of current is aπ\frac{\sqrt{a}}{\pi} A. The value of a is