Science Skills Flashcards
Define an independent variable
The one variable that you change
Define a dependant variable
The variable that you measure
Define a control variable
Any variable you keep the same to make it a fair test
Define directly proportional
If one variable increases the other variable increases at the same rate. eg if x doubles then y must double
Define inversely proportional
If one variable increases the other variable decreases at the same rate. eg if x doubles then y must halve
How would you describe a line graph that does not pass through the origin?
A linear graph
Define an anomalous result
An result which does fit the pattern or trend
Define interval
The spacing between measurements eg 0, 10, 20, 30, 40, 50 cm would have an interval of 10
Define range
The maximum and minimum values eg 0, 10, 20, 30, 40, 50 would have a range of 50 - 0 cm
Define resolution
The smallest change that can be measured with a particular piece of equipment
How can the uncertainty in a measurement be measured?
Half of the range
When should you draw a line graph
When both variables are continuous
When should you draw a bar graph
If one of the variables is discrete or categoric
Define a continuous variable
Can be recored as any number eg time, mass, volume
Define a discrete variable
Can be recored only as a certain values eg number of goals in a match, shoe size
Define a catergoric variable
Is recored in words instead of numbers eg colours or types of metal
What does repeatable mean?
Measurements are repeatable when repetition, under the same conditions by the same investigator, gives similar results.
What does reproducible mean?
Measurements are reproducible if similar results are obtained by different investigators with different equipment.
What is meant by random error?
Measurements are affected by random error due to results varying in unpredictable ways; these errors can be reduced by making more measurements and reporting a mean value.
What is meant by systematic error?
Systematic error is due to measurement results differing from the true value by a consistent amount each time.
What is callibration?
Checking an instrument is displaying a known value i.e ice melts at 0 degrees.
What is parallax error?
Parallax error is caused by a scientist not reading the measurement at eye level
What is peer review?
Where other scientists check data/theories before they are published.
Publications in the media are not subjected to peer review - this often means that the reports are?
Oversimplified, inaccurate or biased
What prefix does k represent?
kilo - x 1,000
What prefix does G represent?
Giga - x 1,000,000,000
What prefix does lowercase m represent?
milli - divide by 1,000
What prefix does captial m represent?
mega - x 1,000,000
What letter is used to represent the prefix micro?
? - divide by 1,000,0000
What prefix does captial n represent?
nano - divide by 1,000,000,000
What does accurate mean?
An accurate measurement is one that is close to the true value.
What does precision mean?
Measurements are precise if they cluster closely.
What equation represents a linear graph?
y = mx + c
Why is perception of risk often very different than measured risk?
Could be influences such as familiar vs unfamiliar risk, visible vs invisble hazards, voluntary vs imposed risks.
What does order or magnitude mean?
To the nearest power of ten - e.g a roof is closer to 10 m long than 100 m long or 1 m long
