MCQ
When a voltage measuring device is connected to AC mains, the meter shows the steady input voltage of 220V. This means,
  • A
    Input voltage cannot be AC voltage, but a DC voltage.
  • B
    Maximum input voltage is 220V.
  • C
    The meter reads not v but < v2 > and is calibrated to read $\sqrt{<\text{v}^2>}$.
  • D
    The pointer of the meter is stuck by some mechanical defect.

Answer

  1. The meter reads not v but < v2 > and is calibrated to read $\sqrt{<\text{v}^2>}$.​​​​​​​

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