Question

Five observers have taken a set of independent voltage measurements and recorded as 110.10 V, 110.20 V, 110.15 V, 110.30 V and 110.25 V. Under the situation mentioned above, the range of error is

1. ± 0.3
2.  ± 0.1
3. ± 0.2
4.  ± 1.0

Answer 1

Correct Answer - Option 2 :  ± 0.1

Range of error:

= ± |Exterme reading - Average reading|

Average reading 

\(\frac{{110.10{\rm{ }}V + 110.20{\rm{ }}V + {\rm{ }}110.15{\rm{ }}V + 110.30{\rm{ }}V + {\rm{ }}110.25{\rm{ }}V}}{5}\)

= 110.20

Range of error

= ± |110.30 - 110.20|

= ± 0.10

Alternate method:

\(RE = ±\frac{{Max - Min}}{2}\)

\(RE = ±\frac{{110.30 - 110.10}}{2}\)

= ± 0.1