Measurement method & errors

 Method of measurement:

   1. Direct method 

    2. Indirect method 

🔘 Direct method : In these method , the unknown quantity is directly compared against a stander . Direct method are quite common for the measurement of physical quantities like length , mass,   etc

🔘 Indirect method : these method  are must of case are inaccurate because factors . They are also less sensitive.

Errors of measurement

 1. Gross error: This class of errors mainly covers human mistakes in reding instruments and recording and calculating measurement results . The responsibility of the mistake normally lies with the exprement . The exprementer may grossly misread with the system. 

2. Systematic error : This errors are type are divided in three categories  ￫ 

i) instrumental errors : This errors mainly due to i herent shortcomings in the instrument . Misuse of the instrument . And loading effect of instruments.                  

ii) environmental errors : This errors are due to conditions external to measuring device including condition in the area surrounding the instrument . These may be effects of temlratempe pressure , humidity , dust , vibrations  or of external electric fields or magnetic fields .

iii) observational errors  : They arr many sources of observational errors.           

3. Random error : These errors are due to a multitude of small factors. we change the fluctuate from one measurement to another and are due surly to chance . The quantity being measured is affected by many happenings throughout the universe . We are aware of and account for sonsof the factors influencing the mesuremeasu, but about the rest we are unaware . The happenings or disturbance about which we are unaware are lumped tigetoge and called random . Hence the errors caused by this heppeniha are called Random errors.