NET, IAS, State-SET (KSET, WBSET, MPSET, etc.), GATE, CUET, Olympiads etc.: Physics MCQs (Practice_Test 28 of 35)

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  1. Twelve equal wires each of resistance 6 0 form a cube. The resistance between the two diagonally opposite comers will be
    1. 3 W
    2. 4 W
    3. 5 W
    4. 6 W
  2. The area of circular coil with 2000 turns is 10 cm2. Its place perpendicular to a magnetic field of 0.3 Wb⟋m2, is rotated by 180. The change in the magnetic flux is
    1. 1.2 Wb
    2. -1.2 Wb
    3. 0.6 Wb
    4. -0.6 Wb
  3. Ratio waves of wavelength 360 m are transmitted from a transmitter. The inductance of the coil which must be connected with a capacitor of capacity 1.2N F in a resonant circuit to receive these waves will be approximately.
    1. 103H
    2. 102 H
    3. l. 0 − 4 H
    4. 10 − 8H
  4. Which of the following Law illustrate the fact that the strength of the induced emf developed from a magnetic field depends upon the rate of change of magnetic flux or magnetic induction?
    1. Faraday՚s law of electromagnetic induction
    2. Lenz՚s law
    3. Newman՚s law
    • Select the correct answer using the codes given below
      1. 1 alone
      2. 1,2 and 3
      3. 2 and 3
      4. 1 and 3
  5. The natural frequency of a circuit containing a condenser, resistance and inductance, all in series, is given by Consider the following statements in this regard.
    1. When R2 > 4L⟋C the discharge is dead beat or non-oscillatory.
    2. When R2 = C the discharge is critically damped.
    3. When R2 < C, the discharge is oscillatory.
    • Of these statements
      1. 1,2 and 3 are correct
      2. 1 and 2 are correct
      3. 2 and 3 are correct
      4. 1 and 3 are correct
  6. Consider the following statements regarding ac circuit having an inductance and a capacitance
    1. Parallel resonance circuit is used for wireless reception.
    2. Parallel resonance circuit works as a perfect choke for ac and therefore is called a rejector.
    3. Series resonance circuits have special importance in transmission systems.
    4. It, series resonance circuit, current and emf are ire phase and hence called acceptor circuit.
    • Of those statements
      1. 1,2 and 4 are correct
      2. 2,3 and 4 are correct
      3. 1 and 3 are correct
      4. 2 and 4 are correct
  7. Current in a coil of 1.5 H increases as I = 4 sin (2t) amperes. During the time the current changes from 0 to 4 A, the amount of energy spent will be
    1. 24 J
    2. 12J
    3. 8 J
    4. 6 J