random and systematic errors

Question 1

What are systematic errors

Answer 1

Systematic errors are measurements that are either always too large, or always too small, by the same amount.

Question 2

types of systematic error

Answer 2

Poor technique (e.g., carelessness with parallax when sighting onto a scale)

zero error of an instrument (e.g., a ruler that has been shortened by wear at the zero end, or a newton metre that reads a value when nothing is hung from it).

Poor calibration of an instrument (e.g., every volt is measured too large)

Question 3

Systematic error stats

Answer 3

Systematic error:
Is constant in sign (always too big or always too small) and in constant size
Can be totally eliminated if we know its size and sign
Cannot be reduced in size by finding the average of repeat readings
Usually caused by limitations in the equipment being used

Question 4

Random error stats

Answer 4

Random error:
Varies in sign (can be too big or too small) and varies in size
Cannot be totally eliminated
Can be reduced in size by averaging repeat readings
Usually cause by limitations in the skill of the person performing the experiment

Question 5

accuracy vs precision

Answer 5

Accuracy is how close a measured value is to the actual value
Precision is how close the measured values are to each other