Question

When a voltage measuring device is connected to ac mains, the meter shows the steady input voltage of $220\,V$. This means

• A. input voltage cannot be ac voltage, but a dc voltage
• B. maximum input voltage is $220\,V$
• C. the meter reads not V but and is calibrated to read $\sqrt{< V^{2} >}$
• D. the pointer of the meter is stuck by some mechanical defect

Answer 1

Answer: (C)

the meter reads not V but and is calibrated to read $\sqrt{< V^{2} >}$

Answer 2

The voltmeter connected to ac mains is calibrated to read root mean square value or virtual value of ac voltage,