Give the classification of the errors used in measuring instrument & state the reason for their occurrence.

1 Answer

Answer :

Types of errors in measuring instruments: 

A) Gross error: These are due to mistakes on the part of person using the instrument. 

B) Systematic Error: 

i) Instrumental Error: These errors are caused due to the mechanical structure of measuring instrument. a) Inherent shortcomings of instruments: Instrument may read too low or too high. b) Improper use of instruments: Improper handling e.g. overloading, overheating, failure to adjust zero, use of high resistance leads. c) Loading effect: cause distortion in original signal. 

ii) Environmental Error: These are because of surrounding conditions such as temperature, pressure, humidity, dust, vibrations, or external magnetic fields or electrostatic fields. 

iii) Observational Error: Parallax errors, incorrect multiplying factor. 

C) Random error: These persist even after gross and systematic errors are removed. 

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