Error and Uncertainty

Question 1

What are the 2 types of errors?

Answer 1

Random Errors and Systematic Errors

Question 2

Define Random Errors

Answer 2

Cause unpredictable fluctuations in an instrument’s readings as a result of uncontrollable factors
Affects the precision of the measurements, causing a wider spread of results about the mean value
Repeat experiment

Question 3

Define Systematic Errors

Answer 3

Arise from the use of faulty instruments or from flaws in the experimental method
Is repeated every time the instrument is used or the method is followed - affects accuracy of all readings obtained
To reduce systematic errors, instruments should be recalibrated or the technique being used should be corrected or adjusted

Question 4

Define Precision of a measurement

Answer 4

How close the measured values are to each other

Question 5

Define Accuracy of a measurement

Answer 5

How close the measured value is to the true value

Question 6

What are the 3 rules for determining how many significant figures are in a number?

Answer 6

1. Non-zero digits (1-9) are always significant
2. Any zeros between two significant digits are significant
3. A final zero or trailing zeros in the decimal portion ONLY are significant