Errors and uncertainties: Every physical measurements are uncertain or imprecise to a few extent. It is very difficult to eliminate all possible errors or uncertainties in a measurement. The error may occur due to
(1) negligence or inexperience of a person
(2) the faulty apparatus
(3) inappropriate method or technique
The uncertainty may occur due to inadequacy or limitation of an instrument, usual variations of the object being measured or usual imperfections of a person’s senses. However, the uncertainty is also regularly described as an error in a measurement. There are two major styles of errors.
(i) Random error
(ii) Systematic error
Random error is said to occur when repeated measurements of the amount, give different values under the equal conditions. It is due to some unknown causes. Repeating the measurement several times and taking an average can reduce the effect of random errors.
Systematic error refers to an effect that influences every measurements of a particular quantity equally. It produces a consistent difference in readings. It occurs to a few definite rule. It may occur due to zero error of instruments, poor calibration of instruments or incorrect markings etc. systematic error can be reduced by comparing the instruments with a different which is known to be more accurate. Thus for systematic error, a correction factor can be applied.
