Module 1 - Practical Skills And Definitions

Question 1

Accuracy def

Answer 1

A measurement result is considered accurate if it is judged to be close to the true/acceptable range
- to do with the numerical data values

Question 2

Anomaly(outlier) def

Answer 2

Value in a set of results that is judged not to be part of the inherent variation

Question 3

Control variable def

Answer 3

Variables other than the independent and dependent variables which are kept the same

Question 4

Dependent variable def

Answer 4

Variable which is measured whenever there is a change in the independent variable

Question 5

Independent variable def

Answer 5

Variable which is deliberately changed or selected by the person in the planning of a practical activity

Question 6

Line of best fit def

Answer 6

A line drawn on a graph that passes as close as possible to the data points. It represents the best estimate of the underlying relationship between the variables

Question 7

Precision def

Answer 7

A quality denoting the closeness of agreement between measured values obtained by repeated measurements
- to do with the data values and numerical data

Question 8

Random error def (not used much in exams)

Answer 8

Error in a measurement due to small uncontrollable effects

Question 9

Range (of a variable) def

Answer 9

The maximum and minimum values of the independent or dependent variables

Question 10

Repeatability def

Answer 10

Precision obtained when measurement results are produced in one laboratory, by a single operator, using the same conditions, over a short timescale

Question 11

Reproducibility def

Answer 11

precision obtained when measurement results are produced by different laboratories and therefore by different operators using different pieces of equipment

Question 12

Resolution def

Answer 12

smallest change in the input quantity being measured by a measuring instrument that gives a perceptible change in the reading of the measuring instrument

Question 13

Systematic error def

Answer 13

error due to the measured value differing from the true value by the same amount each time

Question 14

Uncertainty def

Answer 14

interval within which the true value can be expected to lie, with a given level of confidence or probability

Question 15

Validity (of an experiment) def

Answer 15

suitability of the method used to answer the question being asked
- to do with the method