What is experimental error and percentage error?

Answer 1

Experimental Error:
is using methods and or instruments which is are not totally suited to conduct a particular experiment validly.
e.g. using a contaminated source of a liquid, say water (and or a faulty thermometer) to measure the boiling point temperature for the liquid (e.g. water) would cause experimental errors as the liquid in it's pure uncontaminated form could boil at a different temperature from the contaminated water and or a faulty thermometer will not record the boiling temperature correctly. Also conducting the experiment at altitude would cause an experimental error.

A Percentage Error:
is simply that, for example as pure uncontaminated water boils at sea level at 100 degrees Celsius am immersed thermometer should read an indicated 100 degrees Celsius if it reads 92 degrees Celsius you would have a 8% (low) error reading by the thermometer. If you used a different liquid who's boiling point was say 50 degrees Celsius and the thermometer read 53 you have a 6% (high) error. e.g. Theoretical boiling of 50 divided by measured 53 multiplied by 100 for percent = 106% therefore a percentage error of 6% high as 106% (measured value) - 100% (Theoretical Value) = 6% (high)

Answer 2

Experimental Error:
An error is a bound on the precision and accuracy of the result of a measurement.
Two types of Experimental Error:
(i)statistical error : Statistical error is caused by random fluctuations in the measurement apparatus
(ii)systematic error:systematic error is caused by an unknown but nonrandom fluctuation.

Percentage Error (approximation erro)
This is due to rounding up of numbers, i.e. rounding pi to 3.412 etc etc.


http://en.wikipedia.org/wiki/Experimental_error

http://en.wikipedia.org/wiki/Percentage_error