1. Practicals

Question 1

advantages of using a computer to collect data

Answer 1

allows continual data collection
less risk of error, removes human error
allows easier/direct/immediate data analysis
person does not need to be present
reduce bias
results not subjective

Question 2

independent variable

Answer 2

only variable that should be changed throughout an experiment

Question 3

controlled variable

Answer 3

any other varibables that may affect the results of the experiment that need to be controlled or monitored

Question 4

dependent varibable

Answer 4

the variable that is measure to determine the outcome of an experiment

Question 5

method limitation

Answer 5

any experimental design flaw or fault in the method - affects the accuracy of the results
limitations must be identfied and removed/corrected

Question 6

accuracy

Answer 6

how close a reading is to its true value
reduced by the presence of errors - BAD THING
faulty instruments or flaws in experimental design produce systematic errors that are repeated every time its used
unexpected changes in environement can produce random errors that are different every time the experiment is carried out

Question 7

precision

Answer 7

how similar repeat readings/measurements are to each other
results that are tightly clustered together = precise
reflected in the values recorded - measurements to a greater number of dp = more precise

Question 8

reliability

Answer 8

experiments that are repeated many times to ensure results are reliable

Question 9

validity

Answer 9

the other variables in the experiment are identfied and controlled in otder to ensure the validity
testing what the experiment is supposed to be testing