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Gross Error Mainly covers human mistakes misreading of instrument, incorrect adjustment and improper application of

instruments, and computational mistakes Responsibility lies with the experimenter

Examples: Due to overs g t, one may rea .5 to .5 , During recording, one may read 25.8 0C and write 28.5 0C.

e r mat emat ca ana ys s s mposs e

How to avoid it ? Great care should be taken while reading and recording the data. Several readings should be taken, preferably by different experiment.

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Systematic Error Mainly divided into three categories1. Instrumental 2. Environmental 3. Observational

1. Instrumental Error Due to inherent shortcomings of Instruments Due to misuse of the Instruments Due to the loading effects of Instruments

Can give misleading results when connected across two point in a high-

resistance circuit. The same, when connected in a low-resistance circuit,may give more dependable readings

s ue to t e oa ng ect

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2. Environmental Error

Due to the conditions external to the measuring device i.e, areasurroundin the instrument.

Temperature, pressure, humidity, dust, vibrations or magnetic/electric field

3. Observational Error

Due to the Parallax effect incurred by the line of vision.

Can be avoided by placing the pointer and the scale in the same plane

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Random Error Due to unknown causes and occur even when all systematic errors havebeen accounted for.

They become important in high-accuracy work

readings and using statistical means to obtain the best approximation of the true value of measurand. Also known as the Residual Error .

Revise the followin terms: Mean, Deviation, Average Deviation, Standard Deviation, Variance