Question

Four independent observations recorded voltage measurement of 110.02 V, 110.11 V, 110.08 V and 110.03 V. The average range of error will be
1. 110.06 V
2. 0.05 V
3. ± 0.045 V
4. ± 0.9 V

Answer 1

Correct Answer - Option 3 : ± 0.045 V

Concept:

Range of error \( = \pm \;\frac{{\left( {{V_{{\rm{max}}}} - {V_{{\rm{avg}}}}} \right) + \left( {{V_{{\rm{avg}}}} - {V_{{\rm{min}}}}} \right)}}{2}\)

\( = \pm \;\frac{{{V_{{\rm{max}}}} - \;{V_{{\rm{min}}}}}}{2}\)

Calculation:

V_max  = 110.11 V

V_min  = 110.02 V

Range of error \( = \pm \;\frac{{{V_{{\rm{max}}}} - \;{V_{{\rm{min}}}}}}{2}\)

\( = \; \pm \;\frac{{110.11 - 110.02}}{2} = \; \pm 0.045\;V\)