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When a voltage measuring device is conne...

When a voltage measuring device is connected to a.c. 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 metre reads not V but `lt V^(2) gt` and is calibrated to read `sqrt(lt V^(2) gt)`

D

the pointer of the metre is stuck by some mechanical defect.

Text Solution

Verified by Experts

The correct Answer is:
c
(c) : The AC voltmeter is calibrated to read root mean square value of AC voltage `sqrt(lt V^(2) gt )` not instantaneous voltage V.
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