Question

What is the significance of tolerance value in measuring devices? Use a device for a measurement as an example to explain your answer.

Answer 1

To measure the variables such as temperature, pressure & compositions and so on without an error
or some acceptable error we need to know the tolerance value in measuring devices. It is a permissible
or acceptable limit of error in the measured variable. To get near to accurate and more precise
results in the measured quantity we should know the tolerance.
The tolerance values vary from instrument to instrument, based upon design factors.
For example consider thermometer, here the measured variable is temperature
and the tolerance value for this thermometer is +0.2^oC
Now assume you measured the temperature of water to be 35.8^oC but actual
temperature of water is 36^oC. From this we can understand that there is an error
of 0.2 in the reading so, you add up the tolerance value to get the accurate answer.