The document discusses using blood splatter analysis to determine the height of an attacker based on drops of blood found at a crime scene. It outlines collecting data on the size of blood drops and relating it to the height through mathematical calculations and graphical displays. The goal is to write a scientific report analyzing whether it is possible to estimate the attacker's height from the size of the blood drops on the floor. It also mentions exploring how the angle of impact affects blood splatter patterns.

1. Blood splatter
blood stain pattern analysis

2. Blood splatter: find the relationship between height
and blood splatter
Context. A victim has been strangled. A few drops of
blood were found on the floor near her. Blood tests show
that the blood is not the victims. There is blood on the
victim’s knuckles. It has been hypothesised that the victim
gave the attacker a bloody nose or lip and that the blood
dripped onto the floor. Is it possible to find the height of the
attacker from the size of the blood drop?
Write up your plan/ method, analysis and conclusions in a
scientific report this must include graphical displays of data
Data may be collected in small groups but the report and
calculation must be done individually.

3. Outcomes Grade
P criteria M criteria D criteria
1
carry out
mathematical
procedures involving
units, numbers,
areas, volumes,
indices, formulae
and equations in a
practical laboratory
situation
explain how the use
of some operations
can give skewed
information and
how errors may
occur
explain the use of
negative indices in
the stages of
making serial
dilutions
2
plot and interpret
linear and non-linear
graphs from primary
and secondary
experimental data
explain why
different graphs are
used to present
scientific data and
how errors may
occur
evaluate the
usefulness of
graphs in displaying
the results of
scientific
experiments
3
record and display
scientific data
appropriately,
indicating any errors.
justify the levels of
accuracy in the use
of particular types
of data collection
methods in
laboratory
experiments.
evaluate the
appropriateness of
the methods used
to record and
display data.

4. Extension
What effect does the angle have on the blood splatter
pattern?

7. Angle (°) Width (mm) Length (mm) Sin-1(W/L)
90
80
70
60
50
…etc.

9. Source: http://science.howstuffworks.com/bloodstain-pattern-analysis3.htm