Measuring instrument?

Question

How can the precision of a measuring instrument, like a meter stick, be increased?

Answer 1

By making it from a material that is impervious to heat and cold, doesn't bend when dropped or, has a way of reforming itself if warped (as in a type of metal memory).  Has an auto calibration system.

Answer 2

You can calibrate it by comparing it against a standard of some sort, or another instrument with known accuracy.

The meter stick, you would have to find a reference standard and compare it with your stick at various points along the scale, write these down, then when making a measurement, use those values to apply a correction.

Example, if you compared your stick with a standard and found it read 100.2 cm instead of 100 cm and 50.1 cm instead of 50, then it appears to have a fixed errror of +0.2%, ie, high.

So if you measure an object at 76.4 cm, the actual reading would be

76.4 x 0.998 or 76.24 cm

For some instruments, like  a voltmeter, it is possible to compare it against a reference standard, and then adjust the reading via internal controls, so it reads more accurately.

Eg, a voltmeter may read 1% high at 20 volts, and 10 volts. So you open it up and find a gain adjustment pot for the 20 volt scale and adjust it a little so the meter reads accurately.

Of course there are other factors affecting accuracy, and you are stuck with some  of these:

Noise

Temperature drift

Zero offset

Gain error

resolution error

repeatability error

Position sensitivity

Aging error

Answer 3

You need to make sure that the meter stick is not warn or damages.It should not bend, warp or stretch.

You need to read it accurately, to the nearest 0.5mm, by estimating between the smallest divisions. Make sure the ends are not worn and that one knows to start at the zero, not the one.(zero offset) Do the divisions start right at the very end.

The stick needs to be made of a material that does not change significantly when heated to any temperature that it might be used in. It needs to be calibrated against a known meter, and divided accurately into the cm amd mm