2. BTEC National Certificate in Applied science
(Forensic Science)
Unit 3 Scientific investigation
Introduction
All scientists need to have good investigative skills and this unit develops these
essential skills. Working in science often means teamwork but there are many
instances of independent work. In this unit, learners will have to make the best use
of the laboratory time allocated by the tutor. Learners may be asked to carry out a
practical investigation designed by somebody else or to suggest ways of doing an
investigation themselves. The practical investigation is designed to allow learners to
show their science knowledge and practical skills. After discussion with the tutor
learners will be asked to plan, carry out and analyse the results of their investigation
and present it as a scientific report.
The topic learners choose for investigation will depend on the endorsed title they are
following. The emphasis in this unit is on the learners’ ability to formulate a relevant
hypothesis that they would be able to test experimentally, to plan and execute their
ideas and to deal with the results. Learners may need to use questionnaires but these
will only be part of their research. This is a practical unit and one project will be
used to cover all the learning outcomes, although learners may repeat their
experiment several times in order to collect accurate data.
As in an industrial laboratory, learners will be monitored by the tutor right from the
start of the procedure. Assessment will be on the final report and will take into
account how learners carry out their practical work, their awareness of health and
safety issues and how accurately and honestly they record their results.
Learning outcomes
On completion of this unit a learner should:
1 Be able to formulate a relevant hypothesis and plan an investigation relevant to the area of study
2 Understand the scientific principles involved in the investigation and be able to undertake the
planned investigation
3 Be able to collect, collate and analyse the results from the investigation using appropriate
techniques and present them in an accepted format
4 Understand and interpret results from the investigation and present them in a report in an
accepted scientific format including any applications and implications of science.
4. Assessment criteria & description Evidence needs Assignment
P1
M1
State the objectives and
hypothesis of the investigation
and present a working plan for the
experiment including health
and safety assessments
Analyse the research information
obtained and discuss how it is
relevant to
the planned experiment
Produce a plan
in the form of a
report
Present your
research findings
to the class,
demonstrating the
experimental
procedure. List
references.
(1)
Task 1
Write a plan for your investigation.
Include what aspect affecting the resistance
of the wire you want to work on. State
objectives and hypothesis and describe the
experimental procedure/technique
Task 2
Discuss the research material found. Is it enough to
solve your research targets. How reliable is it.
D1
Appraise the different
approaches considered for the
investigation and justify the
hypothesis, experimental
procedures and recording
methods chosen
As part of plan
include
theory/background
info. Also risk
assessment in
report
Task 3
Justify elements of the plan eg hypothesis, chosen
method and why other methods were rejected.
P2
Demonstrate the required
manipulative skills to assemble
relevant equipment and materials
and safely carry out the planned
investigation
Perform a demo
within your group
to the class
(2)
Show that you are able to carry out practical accurately
and reliably. Demonstrate sound practical skills. Also
show how you will record results.
M2
M3
Explain how accuracy and
precision are ensured in the
investigation
Review experimental progress,
modify practical procedures if
necessary, and justify the use of
experimental techniques to
increase the accuracy,
reliability and validity of results
obtained
Prepare a poster
and/or
presentation about
your work so far
and present to
class
Write a summary
about what you’ve
learnt from the
conference
(3)
Task 1
Describe how you ensure accuracy and
precision in your work.
Task 2
Think about what you’ve learnt from the
conference in task 1. will you stick to your
method or make changes
D2
Evaluate the effectiveness of the
investigative procedures in terms
of accuracy and precision and
suggest how these could be
improved
Make a report to
Justify whether
you adopt or reject
each
improvement.
Task 3
Discuss possible ways to improve the
accuracy and precision of your methods.
Assessment criteria & description Evidence needs Assignment
P3
D3
Assemble equipment, carry
out the planned investigation,
record the results and analyse
the data collected
Analyse the data, justifying
the
statistical methods chosen
and relating the findings to
scientific principles and
applications
Collect data in
tables & graphs.
Ensure units are
included in
table.
(4)
Task 1
Data Analysis (for P3 & D3)
P4
State and explain the
conclusions in a report using
accepted scientific protocol
and language, including
presentation of relevant
research resources.
Produce a scientific
report, following
scientific format,
including references
& bibliography
(5)
Task 1
Writing the final report
M4
Justify the conclusions made,
drawing on primary and
secondary research data.
Write a conclusion.
Say how it is justified
and does data support
it. Relate back to
assignment 1.
Task 2
Conclusions
D4
Evaluate the outcomes of the
investigation using scientific
protocols
An evaluation of the
results. Mention
sources of error and
how they were kept to
a minimum. Evaluate
the conclusion – how
certain are they. Was
your hypothesis
correct?
Task 3
Final Evaluation
5. Scenario
You are investigating ways to reduce the power consumption of overhead power lines transferring
electrical energy from power stations to the home. To do this you need to reduce energy lost as heat by
reducing the resistance of the wire used. You need to investigate how resistance is affected by various
factors.
Task 1 Choosing a topic and researching it
P1 State the objectives and hypothesis of the investigation and present a working plan for the experiment
including health and safety assessments.
You need to complete the following task
• Decide what aspect affecting resistance you want to work on. Share this information with the
others in the class.
• What is the nature of the investigation?
• State your objectives and hypothesis
• Describe what type of experimental research you need to do (e.g. laboratory)
Deadline:________________
Assignment 1 - Planning
6. Task 2- Evaluating the research
M1 Analyse the research information obtained and discuss how it is relevant to the planned
experiment
You need to complete the following task
• Collect all the relevant research material – yours and other students’.
• List the problems you need to solve to answer your research targets.
• Do you now have all the information you need? How valuable is the research done so far?
(Assess each piece of information)
• Do you need more information? If so, how and when are you going to get it?
Deadline _________________
Task 3- Planning the investigation. (P1 and part D1)
P1 State the objectives and hypothesis of the investigation and present a working plan for the experiment
including health and safety assessments.
And part of
D1Appraise the different approaches considered for the investigation and justify the hypothesis,
experimental procedures and recording methods chosen
You need to complete the following task
• List the aims of your investigation – how you will know how the investigation has succeeded?
What is your hypothesis?
• Consider options for tackling the research. Give advantages and disadvantages. Consider what
resources will be required and any costs.
• Describe the details of experimental design and controls, the proposed analytical techniques to
be used, your assessment of possible errors in practical work.
7. • Justify the hypothesis, experimental procedures and recording methods chosen. Confirm your
decision with the lecturer.
• Produce a detailed plan for your investigation, including health and safety assessments.
• Health and safety risk assessments should include descriptions of how you will
eliminate/minimise any identified risks;
Deadline _________________
Scenario
Having researched and planned an investigation into one aspect affecting resistance of a wire, you now
have the chance to carry out the practical work. Your initial findings will be reported to the rest of the
class.
Task 1 The practical investigation.
P2 and P3 (practical part)
P2 Demonstrate the required manipulative skills to assemble relevant equipment and materials and
safely carry out the planned investigation
And
P3 Assemble equipment, carry out the planned investigation, record the results and analyse the
data collected
Having scientifically planned your investigation, it is time to apply those principles by doing the
experimental work.
You need to complete the following task
• Assemble the relevant equipment and materials;
• Adhere to health and safety requirements;
• Manipulate and observe experiments skillfully
• Use appropriately the instruments and techniques for taking measurements;
• Record results with accuracy, integrity, precision;
• Maintain a working laboratory book
Assignment 2 - The Practical investigation
8. Your records should include:
• health and safety issues
• what support you rely on
• how you cooperate with others
• how you revise your plan as you go along
Deadline__________________
Scenario
During your work on assignment 2, you will be attending a science conference to review your progress.
Scientists regularly meet to discuss their latest progress. Conferences are less formal than publishing a
research paper. Papers need to be peer-reviewed before publication. Presentations at a conference are
not reviewed beforehand and the audience is expected to provide constructive criticism and
suggestions.
You will present your findings so far to the rest of the class. They will help you review your progress
and may use some of your ideas in their own research.
Posters
Information about the research is assembled to make a display. Other researchers can read the work at
their leisure and question the researchers about their work.
This assignment is based largely on the information exchanged at the conference.
Task 1 The conference (M2 and D2, evaluation part)
M2 Explain how accuracy and precision are ensured in the investigation
And
D2 Evaluate the effectiveness of the investigative procedures in terms of accuracy and precision
and suggest how these could be improved
You need to complete the following task
Prepare a poster and/or presentation about your work so far.
Assignment 3 - Reviewing Progress
9. Describe how you ensure accuracy and precision in your work.
Evaluate how effective these measures have been in making your work accurate and precise.
Deadline__________________
Task 2 – Review
M3 Review experimental progress, modify practical procedures if necessary, and justify the use of
experimental techniques to increase the accuracy, reliability and validity of results obtained
You need to complete the following task
Write a summary of what you have learned from the conference:
1. What have you learned about your own work? Could you improve the techniques or are you
justified in repeating the same methods?
2. How is the rest of the class progressing? If anyone is doing better than you in any respect – how
can you learn from their methods? If anyone is failing to meet their targets is there any way you
can help them (without jeopardising your own work)?
3. Discuss how the collaboration is working and what problems have occurred. Describe how the
work has met or will meet its targets. Include your contributions. Suggest and agree ways to
improve.
Deadline__________________
Task 3 – The practical investigation (D2 ‘improvements’ part)
D2 Evaluate the effectiveness of the investigative procedures in terms of accuracy and precision
and suggest how these could be improved
10. Assignment 4 – Data analysis
You need to complete the following task
Discuss possible ways to improve the accuracy and precision of your methods.
Analyse how effective each improvement would be.
Justify whether you adopt or reject each improvement.
Deadline__________________
Scenario
As you collect more and more raw data, it becomes important to analyse the results. You might find
that one measurement is obviously wrong, and needs to be repeated. You can check your results with
those of the rest of the class, and with the studies you researched in Assignment 1, but you will need to
convert your results into the same format as the other values.
Task 1 – Data analysis. (P3 ‘analysis’ part and D3)
P3 Assemble equipment, carry out the planned investigation, record the results and analyse the
data collected
And
D3 Analyse the data, justifying the statistical methods chosen and relating the findings to scientific
principles and applications
This work is best done as we go along, but towards the end of the investigation you need to make sure
that you can make sense of all the data collected.
You need to complete the following task
Collect your data into tables and graphs. Take care to show:
• organisation of data eg class intervals, tallying;
• correct units of experimental quantities used;
• fitness for purpose of methods used;
• repeatability;
• sources and magnitudes of errors in reading taken
• assessment of experimental accuracy and precision;
11. What do your data show you? You need to process and analyse the raw data e.g. mean, standard
deviation, student’s t-test. Particularly useful is establishing that two results are significantly different.
Make sure your calculations are accurate.
It will be useful to compare your results with any values you can find in published studies. Assess the
information sources you use:
• is the source relevant?
• if so, does it support or contradict your results?
DEADLINE______________________
Assignment 5 – Writing the report
Scenario
It is time to start writing your chapter of the class’s book on resistance of a wire.
There is a lot you can write already – based on your initial literature research.
As you collect and analyse more data, your conclusions and contribution will become more and more
substantial.
Having done all the hard work, give your efforts the report they deserve!
Task 1 Writing your final report.
P4 State and explain the conclusions in a report using accepted scientific protocol and language,
including presentation of relevant research resources.
You need to complete the following task
Write your scientific report of the investigation:
• Use correct scientific protocol i.e. structure, format;
• Use correct scientific language and terminology i.e. past passive tense;
• Include a section for relevant references and bibliography;
12. • Present your data in an appropriate format, to an appropriate degree of precision, and using
correct units.
Deadline__________________
Task 2 – Conclusions
M4 Justify the conclusions made, drawing on primary and secondary research data.
You need to complete the following task
Read over your conclusions again.
• How are they justified?
• What experimental data supports your conclusions? Do any of your experiments contradict your
conclusions; and if so, why have you ignored these results?
• How do your conclusions relate to the reports you researched in Assignment 1?
Deadline__________________
Task 3 – Final evaluation
D4 Evaluate the outcomes of the investigation using scientific protocols
You need to complete the following task
In conclusion, your report should include:
13. • An evaluation of the results.
• A discussion of sources of error and how to minimize them.
• Evaluation of your conclusions – how certain are they?
• Comparison of your experimental methods and literature investigations.
• Consideration of your hypothesis – did it hold up?
Deadline______________