NEET Online Exam: Physics Quiz!

48 Questions | Total Attempts: 754

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Physics Quizzes & Trivia

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Questions and Answers
  • 1. 
    Alternating current can be defined as current that varies in
    • A. 

      Amplitude and direction

    • B. 

      Magnitude and phase

    • C. 

      Amplitude and time

    • D. 

      time and phase

  • 2. 
    Before a 120-volt dc source can be used to power a 12-volt load, the voltage must be reduced. Which of the following methods can be used?
    • A. 

      A resistor placed in parallel with the load

    • B. 

      A resistor placed in series with the load

    • C. 

      A step-down transformer placed in series with load

    • D. 

      A step-down transformer placed in parallel-with the load

  • 3. 
    Alternating current has replaced direct current in modern transmission systems because it has which of the following advantages?
    • A. 

      Ac can be transmitted with no line loss

    • B. 

      Ac can be transmitted at higher current levels

    • C. 

      Ac can be transmitted at lower voltage levels

    • D. 

      Ac can be readily stepped up or down

  • 4. 
    A waveform is a graphic plot of what quantities?
    • A. 

      Current versus time

    • B. 

      Amplitude versus time

    • C. 

      Voltage versus amplitude

    • D. 

      Magnitude versus amplitude

  • 5. 
    Which of the following properties surrounds a current-carrying conductor?
    • A. 

      A magnetic field

    • B. 

      A repulsive force

    • C. 

      An attractive force

    • D. 

      An electrostatic field

  • 6. 
    Which of the following statements accurately describes the magnetic field surrounding a current-carrying conductor?
    • A. 

      It is parallel to and equal along all parts of the conductor

    • B. 

      It is parallel to and maximum at the most negative part of the conductor

    • C. 

      It is perpendicular to and equal along all parts of the conductor

    • D. 

      It is perpendicular to the conductor and maximum at the most negative point of the conductor

  • 7. 
    Which of the following factors determine(s) the intensity of a magnetic field surrounding a coil?
    • A. 

      The amount of current flow through the coil

    • B. 

      The type of core material

    • C. 

      The number of turns in the conductor

    • D. 

      All of the above

  • 8. 
    When you grasp a coil in your left hand with your thumb pointing in the direction of the north pole, your fingers will be wrapped around the coil in the direction of the
    • A. 

      Voltage potential

    • B. 

      Magnetic field

    • C. 

      Current flow

    • D. 

      South pole

  • 9. 
    The power consumed in a conductor in realigning the atoms which set up the magnetic field is known as what type of loss?
    • A. 

      Hysteresis loss

    • B. 

      Magnetic loss

    • C. 

      Field loss

    • D. 

      Heat loss

  • 10. 
    The magnetic field surrounding a straight conductor is (a) what shape, and (b) is in what position relative to the conductor?
    • A. 

      (a) Linked oblong (b) Parallel

    • B. 

      (a) Concentric circles (b) Parallel

    • C. 

      (a) Linked oblong (b) Perpendicular

    • D. 

      (a) Concentric circles (b) Perpendicular

  • 11. 
    Why is a two-pole magnetic field set up around a coil?
    • A. 

      Because separate lines of magnetic force link and combine their effects

    • B. 

      Because concentric lines of force cross at right angles and combine.

    • C. 

      Because lines of force are separated and bent at the coil ends

    • D. 

      Because separate lines of force are attracted to the two poles of the coi

  • 12. 
    When a conductor is moving parallel to magnetic lines of force, (a) what relative number of magnetic lines are cut, and (b) what relative value of emf is induced?
    • A. 

      (a) Minimum, (b) maximum

    • B. 

      (a) Minimum, (b) minimum

    • C. 

      (a) Maximum, (b) maximum

    • D. 

      (a) Maximum, (b) minimum

  • 13. 
    When the induced voltage in a conductor rotating in a magnetic field is plotted against the degrees of rotation, the plot will take what shape?
    • A. 

      A circle

    • B. 

      A sine curve

    • C. 

      A square wave

    • D. 

      A straight line

  • 14. 
    When a loop of wire is rotated through 360º in a magnetic field, the induced voltage will be zero at which of the following points?
    • A. 

      45º

    • B. 

      90º

    • C. 

      180º

    • D. 

      270º

  • 15. 
    When a loop of wire is rotated 360º in a magnetic field, at what points will the induced voltage reach its maximum (a) positive, and (b) negative values?
    • A. 

      (a) 0º , (b) 180º

    • B. 

      (a) 0º , (b) 270º

    • C. 

      (a) 90º , (b) 180º

    • D. 

      (a) 90º , (b) 270º

  • 16. 
    When a coil of wire makes eight complete revolutions through a single magnetic field, (a) what total number of alternations of voltage will be generated and, (b) what total number of cycles of ac will be generated?
    • A. 

      (a) 32, (b) 16

    • B. 

      (a) 16, (b) 8

    • C. 

      (a) 8, (b) 4

    • D. 

      (a) 4, (b) 2

  • 17. 
    According to the left-hand rule for generators, when your thumb points in the direction of rotation, your (a) forefinger and (b) your middle finger will indicate the relative directions of what quantities?
    • A. 

      (a) Current, (b) Magnetic flux, south to north

    • B. 

      (a) Current, (b) Magnetic flux, north to south

    • C. 

      (a) Magnetic flux, south to north, (b) Current

    • D. 

      (a) Magnetic flux, north to south, (b) Current

  • 18. 
    Continuous rotation of a conductor through magnetic lines of force will produce what type of (a) voltage and (b) waveform?
    • A. 

      (a) Ac, (b) sine wave

    • B. 

      (a) Dc, (b) continuous level

    • C. 

      (a) Ac, (b) sawtooth

    • D. 

      (a) Dc, (b) pulsating wave

  • 19. 
    What is the term for the number of complete cycles of ac produced in one second?
    • A. 

      Period

    • B. 

      Waveform

    • C. 

      Frequency

    • D. 

      Wavelength

  • 20. 
    What is the unit of measurement for frequency?
    • A. 

      Cycle

    • B. 

      Hertz

    • C. 

      Period

    • D. 

      Maxwell

  • 21. 
    A loop of wire rotating at 60 rpm in a magnetic field will produce an ac voltage of what frequency?
    • A. 

      1 Hz

    • B. 

      60 Hz

    • C. 

      120 Hz

    • D. 

      360 Hz

  • 22. 
    An ac voltage of 250 hertz has a period of
    • A. 

      0.004 second

    • B. 

      0.025 second

    • C. 

      0.4 second

    • D. 

      2.5 seconds

  • 23. 
    What is the approximate frequency of an ac voltage that has a period of .0006 second?
    • A. 

      6 Hz

    • B. 

      16.67 Hz

    • C. 

      600 Hz

    • D. 

      1667 Hz

  • 24. 
    Component a is a measure of what quantity?
    • A. 

      Frequency

    • B. 

      Polarity

    • C. 

      Amplitude

    • D. 

      Time

  • 25. 
    Component a differs from component b in which of the following characteristics.
    • A. 

      Frequency

    • B. 

      Polarity

    • C. 

      Amplitude

    • D. 

      Period