This document provides instructions and examples for writing a lab report on measuring resistance of different metals. Key sections that must be included are: background research on resistance, materials used, and importance; a prediction in hypothesis format; organized variables table; procedures and diagrams; observations and analysis tables; graphs of results in Excel with lines of best fit and error analysis; and a conclusion discussing sources of error, variables, results, and proposals for further testing. Examples are given for correctly formatting each section.

1. WRITING YOUR
SUMMATIVE LAB
REPORT

2. My minimum expectation for you is a
level 5-6
CIS expects a minimum level 4.

3. These are the
criteria you
will be
evaluated for
each section

4. These are
examples that
you can use
to understand
EXACTLY
what is
required for
each criteria
you are
evaluated on

5. Add a check
once your
writing
matches the
examples
given and you
have
completed
that criteria

6. Background Research
• Discuss:
• What is resistance?
• What is nichrome and why are we using it?
• Controlled variables and their impact on resistance
should be explained in detail
• Why is it important to know the resistance of materials
(in this case, resistance of metals)
• Impacts on technology advancement, on humans/society
development, safety/efficiency or anything else that is
interesting and relevant.
• Clear & detailed research question ends this section.
• You must include independent & dependent variables

7. Referencing & Research
• Everything must be referenced.
• Use MLA style – there are lots of websites that can help you with
this.
• Use reliable websites, preferably with an author and a
date.

8. Prediction
• Your hypothesis without any mention of ‘I’ or ‘we’
• If…then…because…. is the format you want.
Include reasons & research on independent and dependent
variables and why it is worthwhile to investigate these
factors.

9. Variables
• Use a table to help organize and keep everything nice
and neat.
• List your independent, dependent and controlled
variables, explaining (briefly) why you are using them.
• Make sure you use how you are measuring them – this
includes units!!

10. Procedures & Diagrams
• It is good practice to have a labelled diagram of your set –
up.
• Components:
• Figure # (1, 2, 3, etc)
• Title
• One sentence description of what the image shows.
• See your textbook for an example
• It can be hand-drawn using a ruler or a photograph.

11. Observations
• Qualitative – no numbers, what you saw
• Quantitative – numbers, what you actually measured
• Use tables and tables must be numbered AND have a
title, and an explanation of what the table has.

12. Analysis
• For this lab, you will have to use Excel to graph
your data
• You will use the graph and interpret the different
lines you have.
• You should have 5 lines for each of the wires, and
ideally, at least 5 points to help you see the shape
of the graph.

13. Types of Graphs to Expect
• If your factor was:
• Length
• Your graph will be linear
• Thickness
• Your graph will be non-linear

14. • You will have to do a ‘line/curve of best fit’.
• Each graph will have to have a:
• Line drawn to find a trend (a pattern) and not connect
every dot
• Figure #
• Descriptive title (that is bold and underlined)
• Axis labels
• A legend or some sort of notation to help explain the
different lines
• A sentence or two that describes what the graph is
showing (such as positive/negative trends,
representation of variables, any general conclusion).
• This is written after the title, and is not in bold or underlined

15. Axis Labels
• Include:
• The variable
• The unit it is
measured in
brackets (unit)
• Underlined
variable titles

16. Graph Trends – Linear Relationships
Direct Relationship Inverse Relationship

17. Graph Trends – Non-Linear Relationships
Positive/Direct Negative/Inverse

18. Graph Trends – No Trend
• When there is no
relationship
between variables,
this means that
your factor does not
impact what you
were measuring.
• Your hypothesis
was not valid.

19. Strong v.s. Weak Correlation
Points are close to line of best fit Points are far from line of best fit

20. Line of Best Fit

21. Curve of Best Fit

22. Interpreting Line of Best Fit

23. LET’S PRACTICE!

24. MAKING GRAPHS IN
EXCEL

25. Step 1
• Enter your data,
include titles.

26. • Step 2: Click on
the ‘Charts’ tab at
the top

27. • Step 3:
• Select
‘Scatter’.
• Choose
smooth
marked
non-linear
relationship
• Choose
straight
marked 
linear
relationship

28. • Step 4: You will see your graph displayed, it will look something
like mine.
Current
Voltage

29. • Step 5: Click on the coloured tab next to charts, and
select ‘Chart Layout’

30. • Step 6: Click on one of the lines on your graph.

31. • Step 7: Select the option ‘Trendline’ and click on the very
bottom, ‘Trendline Options’

32. • Step 8: Linear  click ‘linear’. Non-linear  select
something that best fits your line. It will likely be ‘Power’

33. • Step 9: Go to ‘Options’ on the left.
• Select ‘Set intercept = 0’, and ‘Display equation on
chart’

34. • Looking at the different graphing Options  Linear

35. • Looking at the different graphing Options  Logarithmic

36. • Looking at the different graphing Options  Polynomial

37. • Looking at the different graphing Options  Power

38. In the future,
you will have to choose the best graph yourself

39. • Step 10: You will see an equation next to your line of best
fit. The number is what you must keep track of of.

40. • Step 11: Repeat steps 1-10 for each of your lines. You
should have a total of 5 lines, one for each wire.

41. • Step 12:
• ‘Format’
options to
ensure all
axis are
labelled.

42. Slope
This will have a
larger slope (a
higher number)
This will have a
smaller slope (a
lower number)

43. Slope
• Run = independent = voltage
• Rise = dependent = current
Ohm’s Law is R = V/I
• So, we will have to take the inverse of our slope value to
get the resistance for each value.
You are required to show this work in a table and
explain why you had to do this step in your data
analysis.

44. Analysis Explanation
• You cannot rely on the graph to explain the data.
• You must use written explanation of your raw data and
refer to the graph/tables to help the reader understand
your explanation.
• You will explain and comment on the relationships you
see between your independent and dependent variables
for each of your wires.
You will use the words direct/inverse relationship &
strong/weak correlation in your analysis.

45. Analysis Explanation
• For this lab, you should find the resistance for all
5 wires (ideally, they will all be different).
• You will get this from the slope of the line.
• This is found from excel.
• The slope number in the equation is the inverse
resistance if voltage is your independent variable.
• You will make a table to illustrate your measured resistance for
each wire.

46. Calculated Resistances
• You will take your calculated resistances from your graph
equations, and you will do two things with them:
• 1) Error Analysis. Look to the following slides for more
information.
• 2) Graph calculated resistance against the gauge of wire
to find the trend. For this, I will not be illustrating a graph,
as this is something I’d like to see your understanding of.

47. Error Analysis
• In your analysis, you will also do an error analysis.
• This is where you compare your results with results that are
expected .
• What is the theoretical resistance for that wire given by the
manufacturer
• This is done so you can discuss why your data looks the
way it does in comparison to what is already known
about that material’s properties.
• It is also done to figure out where there may be issues in your
experiment (i.e. could your set up be better, did you need to
consider other control variables, etc).

48. Percentage Error
• You will use the formula:
Calculated Resistance
Theoretical Resistance
x 100%
• You want your error values to be as close to 1 as possible
• This means your calculated resistance is very close to what is
expected for that wire at that gauge/length

49. Theoretical Resistance
Data Chart
• Use this table for
your theoretical
resistance
information.
• The wire we used
was NiCr C

50. Outlier Points
• Points that are very far away from your line of best fit, you
must explain what happened/causes it as part of your
discussion of error

51. Conclusion
• It is in paragraphs and has lots of detail!
• Error: if less than 10% error =>90%++ it means the
experiment was successful at getting a valid answer
• Independent variable: Did you manipulate it in a fair way?
Were there any inconsistencies or problems?
• Dependent variable: Did your experiment actually measure
what you intended to measure? Could it have been measured
in another way that would give better results?
• Control variables: were all variables controlled so it was a fair
test? If not, how did that affect the results? Was there anything
you could not control, or materials that could have been better?
• Does your data make sense?
• Propose new areas to test to further get more information
about resistivity of the wires we studied.