The length of a rod as measured in an experiment is found to be 2.48 m, 2.46 m , 2.49 m , 2.49 m and 2.46 m. Find the average length , the absolute error in each observation and the percentage error.

Answer

2.48m ; 0.00m, 0.02m, -0.01 m,
-0.02 m, 0.00m; 0.01 m ; 0.40%

Explanation

Average length
`=(2.48 +2.46 + 2.49 +2.50 +2.48)/(5) = (12.41)/(5)m`
`=2.482 m = 2.48m ("rounded off to 2 places")`
Absolute errors id different measurements are ,
`Deltal_1 = 2.48 - 2.48 =0.00m`
`Deltal_2 = 2.48 - 2.46 =0.02m`
`Deltal_3 = 2.48 - 2.49 =0.01m`
`Deltal_4 = 2.48 - 2.50 =0.02m`
`Deltal_5 = 2.48 - 2.48 =0.00m`
Mean absoulte error `= (Sigma| DeltaL |)/(5)`
`=(0.00 +0.02 + 0.01 + 0.02 +0.00)/(5) =0.01m`
`:." Correct length" = (2.48 +- 0.01)m`
`"Percentage error" =(0.01)/(2.48)xx100 = 0.40%`