Notesale: Turn your study into money

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Unit 14 - Assignment 1 - P1

Unit 14 - Assignment 1 - M1 - Task 2
Equipment list:
•
•
•
•
•
•

Power supply (socket)
...

Voltmeter
Thermometer
...

Heat proof mat
...


Step by step
1
...

2
...

3
...

4
...

5
...


Results
Metal

Copper
Brass
Aluminium

Initial
temperature
(oC)
44
38
21

Final
temperature
(oC)
69
60
26

Values
E = MC Δ ϑ
C = E / (M Δ ϑ)
Copper = 10,800 / (1 Δ 25) = 432 J kg-1 k-1
Brass = 10,800 / (1 Δ 22) = 491 J kg-1 k-1
Aluminium = 11,100 / (1 Δ 5) = 2,220 J kg-1 k-1

Voltage (V)

Current (A)

10
10
10

3
...
6
3
...

The result differences:
Copper = 46 J kg-1 k-1
Brass = 111 J kg-1 k-1
Aluminium = 1307 J kg-1 k-1

My results were different from the actual values as the energy supplied values were too high
...
Also, the room temperature could have affected the temperatures of the metals by increasing
them
...
A number of people were doing the same experiment, so the heat from their
electric beakers would have also increased the room temperature
...
Parallax error is the change in the apparent
position of an object when the position of the observer changes
...
This will cause the calculations to change the final values, which may affect
the results and cause them to be inaccurate
...
Also, the higher or lower the metal purity may affect the specific heat capacity of the metal,
which may cause the calculations to change the final values
...
Another error could be from the mass of the metal
...
To reduce this error, weigh the
metal on several electronic balances, as the balance also may not be accurate
...

To improve the accuracy of the experiment I would have done the tests multiple times to work out
an average value for each metal
...


Unit 14 - Assignment 1 - M1 - Task 3
Equipment list:
•
•
•
•
•
•
•
•

Power supply (socket)
...

Voltmeter
Ice
...

Funnel
Filter paper
Beaker

Method

1
...

2
...

3
...

4
...

5
...

6
...
Make sure that ice is
always melting
...
After five minutes (300 seconds), remove the weighed beaker and replace it with the
original
...
Weigh the beaker filled with the melted ice (water)
...
Take the mass of the beaker to start with and the mass of the beaker to end with to work
out the mass of the melted ice
...
1186kg
Mass of beaker and melted ice: 0
...
0175kg
Current: 3
...
63V
Time: 5 minutes = 300 seconds

Calculations
The energy needed to melt the ice comes from the electrical energy of the heater
...
52 * 8
...
28J
Electrical energy supplied = 9113
...
28 / 0
...


Energy to melt ice = Mass of water * Specific latent heat of fusion of water
9113
...
0175 * 520,759

Discussion
Actual specific latent heat of fusion of water: 334,000Jkg-1
My specific latent heat of fusion of water: 520,759Jkg-1
Difference: 186,759Jkg-1
My value is greater than the actual specific latent heat of fusion of water
...
This may be because the mass of melted ice was too low
...
This
also leads to the waste of thermal energy, as the heater was also touching the filter paper; heating
that up instead along with the funnel (partially)
...
If the ammeter and/or voltmeter is reading the current and/or volts incorrectly, then
there would be a fault in the calculations causing the electrical energy value to be incorrect
...
To reduce this error,
before using the ammeters and voltmeters, check that they are accurate and set to the right setting
and compare them to others to ensure accuracy
...
This would cause the
calculation to be inaccurate as a negative number will be used
...
However, it does not matter if it appears as a
negative number, as long as you ignore the minus symbol and look at it as a positive number; the
digits are the same
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For example, recording the mass of the beaker in grams instead of kilograms
...
To reduce this error, follow the instructions carefully and use the right values in the
right form for the formulas and calculations
...
To reduce this error, weigh the beaker
on several top pan balances
...
Do not use the value that has a big difference
...

This will cause the electrical energy supplied value to be incorrect
...

To improve the accuracy of the experiment I would have done the tests multiple times to work out
an average value for the specific latent heat of fusion of water
...


Unit 14 - Assignment 1 - M1 - Task 3



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