Definitions

Question 1

accurate

Answer 1

a measurement is considered accurate if it is judged to be close to the true value

Question 2

anomalies

Answer 2

results that do not match the pattern seen in the other data collected or are well outside the range of other repeat readings (outliers)

Question 3

bar chart

Answer 3

used when you have a categoric independent variable and a continuous dependent variable

Question 4

categoric variable

Answer 4

categoric variables have values that are labels. For example, types of material

Question 5

continuous variable

Answer 5

can have values (called a quantity) that can be given by measurement (for example, mass, volume, temperature, etc.)

Question 6

control variable

Answer 6

a variable which may, in addition to the independent variable, affect the outcome of the investigation and therefore has to be kept constant or at least monitored

Question 7

dependent variable

Answer 7

the variable for which the value is measured for each and every change in the independent variable

Question 8

directly proportional

Answer 8

a relationship that, when drawn on a line graph, shows a positive linear relationship that crosses through the origin

Question 9

errors

Answer 9

sometimes called uncertainties

Question 10

fair test

Answer 10

a fair test is one in which only the independent variable has been allowed to affect the dependent variable

Question 11

hazard

Answer 11

a hazard is something (e.g., an object, a property of a substance or an activity) that can cause harm

Question 12

hypothesis

Answer 12

a proposal intended to explain certain facts or observations

Question 13

independent variable

Answer 13

the variable for which values are changed or selected by the investigator

Question 14

line graph

Answer 14

used when both variables are continuous. The line should normally be a line of best fit, and may be straight or a smooth curve

Question 15

precise/precision

Answer 15

a precise measurement is one in which there is very little spread about the mean value. Precision depends only on the extent of random errors – it gives no indication of how close results are to the true (accurate) value

Question 16

prediction

Answer 16

a forecast or statement about the way something will happen in the future

Question 17

random error

Answer 17

differences in results due to poor measurements being made. Usually this is because the experimenter does not carry out exactly the same method each time, or because of limitations of the measurement device; these errors can be reduced by making more measurements and reporting a mean value.

Question 18

range

Answer 18

the maximum and minimum values of the independent or dependent variables

Question 19

relationship

Answer 19

the link between the variables that were investigated

Question 20

repeatable

Answer 20

a measurement is repeatable if the original experimenter repeats the investigation using the same method and equipment and obtains the same or precise results

Question 21

reproducible

Answer 21

a measurement is reproducible if the investigation is repeated by another person, using different equipment and the same results are obtained

Question 22

risk

Answer 22

the likelihood that a hazard will actually cause harm

Question 23

systematic error

Answer 23

cause readings to be a value other than the true value, due to results differing from the true value by a consistent amount each time a measurement is made

Question 24

valid

Answer 24

suitability of the investigative procedure to answer the question being asked

Question 25

variable

Answer 25

physical, chemical or biological quantity or characteristic