SKILLS - if actual size given, calculate
Independent variable magnification with the formula:
- variable changed by the investigator on
purpose measured length of specimen ( mm ) x 1000
magnification=
actual ¿ ¿¿
Dependent variable Tables
- variable observed or measured - must always have a heading with three
- results point to the dependent variable variables
- D – dependent - units always appear in column
R – recorded headings
O – observed
M – measured Graphs
Y – y-axis - must always have a heading with three
variables
e.g. to test the effect of increasing sugar - y-axis – dependent variable is
concentration on the growth of plants recorded
- x-axis – independent variable
Reliability
- experiment must be repeated Aim
- sample size must be increased – find - aim identifies the purpose of the
an average investigation
- always starts with to show/determine
Validity etc
- valid if:
control is present Hypothesis
there is only one independent - cannot be “I predict” or “if…then…”
variable meaning that all other - hypothesis = idea or explanation that
variables are controlled you then test through
(therefore there are controlled research/experimentation
variables present) - must mention independent and
dependent variable
Control apparatus - written as a statement showing the
- used to prove that the results obtained relationship between the two variables
are correct and valid - e.g. aphid-infected plants that are
- exactly the same as normal apparatus exposed to ladybugs will have fewer
but independent variable is omitted aphids after a week than aphid-
infected plants which are left untreated
Measuring actual size
Conclusions
- one micron (µm) = one millimetre (mm)
x 1000 - = result/outcome of an act/process
- if scale line given: - not an observation
¿ measured length of specimen ( mm ) x given scale line ( μmm) - state whether your results support or
actual - contradict hypothesis
measured length of scale line (mm)
- if magnification is given:
¿ measured length of specimen ( mm ) x 1000
actual
givenmagnification ( x )
Independent variable magnification with the formula:
- variable changed by the investigator on
purpose measured length of specimen ( mm ) x 1000
magnification=
actual ¿ ¿¿
Dependent variable Tables
- variable observed or measured - must always have a heading with three
- results point to the dependent variable variables
- D – dependent - units always appear in column
R – recorded headings
O – observed
M – measured Graphs
Y – y-axis - must always have a heading with three
variables
e.g. to test the effect of increasing sugar - y-axis – dependent variable is
concentration on the growth of plants recorded
- x-axis – independent variable
Reliability
- experiment must be repeated Aim
- sample size must be increased – find - aim identifies the purpose of the
an average investigation
- always starts with to show/determine
Validity etc
- valid if:
control is present Hypothesis
there is only one independent - cannot be “I predict” or “if…then…”
variable meaning that all other - hypothesis = idea or explanation that
variables are controlled you then test through
(therefore there are controlled research/experimentation
variables present) - must mention independent and
dependent variable
Control apparatus - written as a statement showing the
- used to prove that the results obtained relationship between the two variables
are correct and valid - e.g. aphid-infected plants that are
- exactly the same as normal apparatus exposed to ladybugs will have fewer
but independent variable is omitted aphids after a week than aphid-
infected plants which are left untreated
Measuring actual size
Conclusions
- one micron (µm) = one millimetre (mm)
x 1000 - = result/outcome of an act/process
- if scale line given: - not an observation
¿ measured length of specimen ( mm ) x given scale line ( μmm) - state whether your results support or
actual - contradict hypothesis
measured length of scale line (mm)
- if magnification is given:
¿ measured length of specimen ( mm ) x 1000
actual
givenmagnification ( x )
