Conduction
Explain the process of conduction and investigate the
thermal conductivity of some different metals.
Science Energy
Keywords
Temperature is how hot a substance is and is
measured in degrees Celsius (oC).
Solids have a regular arrangement of particles.
An insulator is a material that is a poor conductor of
heat and electricity.
Lesson outline
Conduction
Temperature and heat
Understanding conduction
Investigating conduction
Temperature and heat E
Temperature is:
● a measure of how hot something is
● measured using a thermometer
● measured in degrees Celsius (oC).
Heat is:
● a measure of the energy in the thermal energy
store of an object
● measured in joules.
Heat and temperature E
Heat is a measure of the amount of
energy in an object's thermal energy
store.
The thermal energy store of an object
depends upon:
● the number of particles
● the energy of its particles
The sparks from a sparkler have a
very high temperature but a
relatively low thermal energy
because they consist of very few
particles.
Heat and temperature E
Why does the water in a warm bath have more
thermal energy than sparks from a sparkler?
temperature = 1000 oC temperature = 50 oC
thermal energy = low thermal energy = high
There are many more particles in a bath of water than in a
sparkler.
C
Heat is a measure of …
A the energy in the thermal energy store of an object
B how hot an object is
C
how easily an object can burn you
C
What unit is temperature measured in?
A degrees Celsius (oC)
B joules (J)
C
newtons (N)
Task 1 Heat and temperature P
a) Draw lines to match the information about heat and
temperature.
a way to measure how hot or measured in degrees
heat
cold something is Celsius (oC)
a measure of the energy in
temperature the thermal energy store of measured in joules (J)
an object
Task 1 Answers P
a) Draw lines to match the information about heat and
temperature.
a way to measure how hot or measured in degrees
heat
cold something is Celsius (oC)
a measure of the energy in
temperature the thermal energy store of measured in joules (J)
an object
Task 1 Heat and temperature P
b) Which beaker has the highest heat (thermal energy)?
Explain your answer.
A B C
Task 1 Answers P
A B C
b) Which beaker has the highest heat (thermal energy)?
Explain your answer.
Beaker C.
The water in all of the beakers is the same temperature meaning
the particles are moving with the same energy, but there is more
water in beaker C so there are more particles.
Lesson outline
Conduction
Temperature and heat
Understanding conduction
Investigating conduction
Understanding conduction E
Thermal energy is transferred from hotter regions
to colder regions.
The bigger the difference in temperature between the
hotter and colder region, the faster energy transfer occurs.
fast energy slow energy
transfer transfer
90 oC 20 oC 90 oC 80 oC
Understanding conduction E
In solids, energy is transferred by conduction.
Metals are good thermal Non-metals are poor thermal
conductors. conductors. We call poor
thermal conductors insulators.
Understanding conduction E
How does conduction occur?
particles in a metal bar
Heating particles transfers energy to them, causing
them to them to gain energy in their kinetic energy store
heat and vibrate more.
Vibrating particles collide with nearby particles
transferring energy and causing them to vibrate more as
well.
C
Which one of these objects will conduct thermal
energy the fastest?
wooden spoon metal plastic knife
A fork B C
C
True or false?
Plastic is a better conductor than metal.
T True F False
Justify your answer
A
Plastic is a poor thermal conductor.
B Plastic is a good thermal conductor.
Task 2 Understanding conduction P
a) Describe the process of conduction.
b) Explain why using a metal mug to drink hot drinks
from would not be a good idea. Use ideas about
conduction in your answer.
Task 2 Answers P
a) Describe the process of conduction.
Heating particles transfers energy to them causing them
to gain energy in their kinetic energy store and vibrate
more.
Vibrating particles collide with nearby particles
transferring energy and causing them to vibrate more as
well.
Task 2 Answers P
b) Explain why using a metal mug to drink hot drinks
from would not be a good idea. Use ideas about
conduction in your answer.
Metals are good conductors of thermal energy. They would
not make a good drinking mug because the metal would
conduct thermal energy from the drink and become hot
which could burn your lips.
Lesson outline
Conduction
Temperature and heat
Understanding conduction
Investigating conduction
Investigating conduction E
We can carry out an investigation into which metal
is the best conductor of thermal energy.
Think about:
Why are drawing pins
attached to the metal rods by
vaseline?
How will you know which
metal is the best thermal
conductor?
What will you need to control
to get valid results?
Investigating conduction E
We can carry out an investigation into which metal
is the best conductor of thermal energy.
Think about:
What is the independent
variable?
What is the dependent
variable?
How could you get accurate
results?
Investigating conduction E
The investigation was repeated three times. The
data is shown below. We need to calculate the
mean for each metal.
Type of Time taken for pin to fall (s)
metal rod
try 1 try 2 try 3 mean
steel 43 46 46
copper 29 33 28
brass 34 35 36
aluminium 41 42 37
Investigating conduction E
Calculating a mean
Type of Time taken for pin to fall (s)
metal rod
try 1 try 2 try 3 mean
45
steel 43 46 46
To calculate the mean, you need to add all of the values
together and then divide by the number of values:
43 + 46 + 46 = 135
135 ÷ 3 = 45
Task 3 Investigating conduction P
a) Calculate the mean for each metal.
Type of Time taken for pin to fall (s)
metal rod
try 1 try 2 try 3 mean
steel 43 46 46 45
copper 29 33 28
brass 34 35 36
aluminium 41 42 37
Task 3 Answers P
a) Calculate the mean for each metal.
Type of Time taken for pin to fall (s)
metal rod
try 1 try 2 try 3 mean
steel 43 46 46 45
30
copper 29 33 28
35
brass 34 35 36
40
aluminium 41 42 37
Task 3 Investigating conduction P
b) Plot the data from the table as a bar chart.
Type of Mean time
metal rod taken for pin
to fall (s)
steel 45
copper 30
brass 35
aluminiu 40
m
Task 3 Answers P
b) Plot the data from the table as a bar chart.
Mean time taken for the pin to fall (s)
Type of Mean time
metal rod taken for pin
to fall (s)
steel 45
copper 30
brass 35
aluminiu 40
m
steel copper brass aluminiu
Type of metal rod m
Task 3 Investigating conduction P
c) Starting with the metal with the highest thermal
conductivity, sort the metals into order of thermal
conductivity.
d) Of the metals tested, which is best one to use to
make saucepans? Explain your answer.
Task 3 Answers P
c) Starting with the metal with the highest thermal
conductivity, sort the metals into order of thermal
conductivity.
copper
brass
aluminium
steel
d) Of the metals tested, which is best one to use to
make saucepans? Explain your answer.
Copper is the best metal to make saucepans because it has
the highest thermal conductivity so will cook food quickly.
Summar Conduction
y
When thermal energy is transferred from a hotter region
to a colder region by particles, this is conduction.
Conduction occurs fastest in solids because the particles
are very close together. Metals are excellent conductors.
We can investigate conduction by timing how long it
takes drawing pins to fall off different metal rods. The
faster the time, the better the conductor.
