A blank nine-step write-up with the correct table headings. Print it for a real lesson and fill it in by hand. See the specimen lab book
Blank write-up: Density
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Study Hack Lab
RP 5 · Physics
Density
Write-up template
Name
Date
Course
GCSE Physics
Board and specification
AQA GCSE Physics (8463), 4.3.1.1AQA GCSE Combined Science: Trilogy (8464), 6.3.1.1Apparatus and techniques: AT 1
Class and teacher
Aim
Determine the density of a regular metal block, an irregular object (is the crown really gold?) and a liquid.
Contents
Plan and risk assessment
Apparatus
Method
Results
Graph
Analysis
Conclusion and evaluation
Make safe and clear up
A blank write-up for use in a real lesson. The headings follow the AQA required practical; the readings are yours to take. Layout v1, practical v2. Original material; not affiliated with AQA, which has not reviewed it.
1 Plan and risk assessment
Density is the mass of each cubic centimetre of a material: density = mass ÷ volume. It depends on what the object is made of, not on how big it is, so it can tell a gold crown from a gold-plated fake.
ρ = m ÷ V
Variables
Independent (you change)
Dependent (you measure)
Control (you keep the same)
Prediction
A second block is made of the same metal but is twice as big. What will its density be?
How can you find the volume of the crown?
The crown looks gold. Gold is 19.3 g/cm³. What do you expect to find?
Risk assessment
Hazard
Harm it could cause
Control
2 Apparatus
Digital balance (resolution 0.1 g) Measures mass.
Metal block (cuboid) The regular object.
30 cm ruler (resolution 1 mm) Measures the block’s sides.
Vernier callipers (resolution 0.1 mm) Measures the block’s sides more precisely.
Model crown The irregular object: is it gold?
Thin cotton thread and thick string To lower the crown into the water.
Eureka (displacement) can on a brick Overflows by the crown’s volume.
Measuring cylinders: 25 cm³, 100 cm³ (×2) and 250 cm³ (resolution 0.5 cm³, 1 cm³, 2 cm³) Measure volumes of water and solution.
Sugar solution (about 150 cm³) The liquid.
Plastic tray and paper towels Catch spills.
3 Method
Write numbered steps someone else could follow. Say what you measure, with which instrument, and how you keep it a fair test.
4 Results
The table is drawn before you measure. Record each reading to the resolution of the instrument, then work out the mean of your repeats, leaving out any anomaly.
The block and the crown
Object
Mass in g
Length in cm
Width in cm
Height in cm
Volume in cm³
Density in g/cm³
Metal block
Crown
Volume of the crown (eureka can) · Refill the can to the spout before every trial.
Trial
Volume of water collected in cm³
1
2
3
Mean
The sugar solution · Mass of solution = reading − mass of the empty cylinder.
Pour
Volume of solution in cm³
Mass of cylinder and solution in g
Mass of solution in g
Empty
1
2
3
4
5
Anomalies
Ring any anomalous result. Say what probably went wrong and whether you repeated it.
5 Graph
Density of the sugar solution · Choose your axes: the independent variable goes on the x-axis. Label each axis with the quantity and unit.
6 Analysis
Volume of the block
volume = length × width × height
Answer
Density of the block
density = mass ÷ volume
Answer
Volume of the crown
mean = sum of the values ÷ number of values
Answer
Density of the crown
density = mass ÷ volume
Answer
Gradient (the density of the solution)
Answer
In kg/m³
1 g/cm³ = 1000 kg/m³
Answer
7 Conclusion and evaluation
Conclusion
Conclusion: what do your results show? Use your own numbers.
Sources of error
For each, say whether it is systematic or random, and how it affected your results.
Resolution of the ruler (1 mm) on sides only 2–5 cm long
Balance not zeroed (zero error)
The thread or string under the water
Drips from the freshly filled can collected with the displaced water
Water left in the spout and on the cylinder wall
Reading the meniscus (eye position and the size of the divisions)
Air bubbles clinging to the crown
Improvement
How could you improve the method? Say why it would help.
8 Make safe and clear up
Empty the water you used for the crown, and the measuring cylinders, into the sink
Dry the crown, the block and the bench, and mop up any spills
Switch off the balance and put the metal block back in the kit tray
Rinse the sugar solution out of the cylinder so it does not go sticky