Everything You Need to Ace Chemistry in One Big Fat Notebook by Jennifer Swanson

SYSTEMATIC ERRORS
A systemic error affects the accuracy of a measurement.
If the instrument that you are using is not properly set, it
cannot give an accurate measurement. CALIBRATION
is when the readings of an instrument are compared to
a known measurement to check its accuracy. This can also
be known as “zeroing” something. For example, if you turn
on a digital scale, does it read zero without anything on
it? Or does it read .01 grams (g) or .02 g? If the reading
is not zero, then the scale is not properly calibrated. This
will affect all of the measurements that you take on
this scale.
Perhaps the scale isn’t digital but is read with a lever
that moves into position. Are you looking at the lever straight
on or at an angle? If you read the lever at a different
angle each time, you will get a different measurement
each time.
A parallax error occurs
when you view the object
from different points.
The correct answer is
indicated by the straight
green arrow and number.
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