Explain Random errors.

Explanation

Random errors
(i) Random errors may arise due to random and unpredictable variations in expermental conditions like pressure, temperature, voltage supply etc.
(ii) Errors may also be due to personal errors by rthe observer who performs the experiment. Random errors are sometimes called change error.
(iii) When different readings are obtained by a person every time he repeats the experiment, personal error occurs.
(iv) For example, consider the case of the thickness of a wire measured using a screw gauge.
(v) The readings taken may be different for different trials. In this case, a large number of measurements are made and then the aritmetic mean is taken.
(vi) If n number of trial readings are taken in an experiment and the readings are `a_(1),a-(2),a_(3)`,..............a_(n)`. The arithmetic mean is
`a_(m)=(a_(1)+a_(2)+a_(3)+.............a_(n))/n`
`a_(m)=1/nsum_(i=1)^(1=n)a_(i)`
Usually this arithmetic mean is taken as the best possible true value of the quantity.