Question

The temperature measured in an experiment was `"64.9"^@"C"`. The theoretical temperature is `"55.0"^@"C"`. What is the percent error?

Answer 1

Percent error = `| "theoretical - experimental"/"theoretical"|"` x 100

In this example, the theoretical is 55.0 Celsius and the measured is the experimental which is 64.9 Celsius.

The difference in terms of absolute value is 9.9:

`| 55.0 - 64.9 |` = `9.9`

`| "9.9"/"55.0" |` = `.18`

`.18` x `100` = `18 %`

The purpose of percent error is to provide a measure of how close you are to an accepted standard.

The error can be attributed to imprecision of instrumentation or due to experimental error or both.

A small percent error such as 5 % validates that the experiment was conducted with precise thermometers or that experimental technique was carefully carried out.

Theoretical values determined after numerous careful experiments are set as a standard value such as the standard kilogram.