A 0–150V voltmeter has an accuracy of 1% of full-scale

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A 0–150V voltmeter has an accuracy of 1% of full-scale reading. The voltage measured by this instrument is 75V. The limiting error is:

1. 1%
2. 2%
3. 2·5%
4. 3%

Correct Option: B

Given voltmeter range 0 – 150V
relative error E_r = 1% = 0·01
The magnitude of the limiting error of the instrument
δA=E_r × V where, V is the true value
= 0·01 × 150
= ·150
The magnitude of the voltage being measured is 75V.
The limiting error or relative error at this voltage is

E_r =	δA	=	·150	= 2%
	V		75