Insulators GCSE Physics Practical

Investigate the effectiveness of different materials as thermal insulators and the factors that may affect the thermal insulation properties of a material.

Students must investigate the effectiveness of various materials as thermal insulators, as well as look at how the number of layers of a specific material affects the insulating properties. A variety of materials could be included for students to test (for example: newspaper, aluminium foil, cotton). Students will use the rate of cooling water method to investigate this.

Equipment (per participant)

• Safety glasses
• 100ml beakers (x 5)
• 250ml beakers (x 5)
• Kettle
• Thermometer (x 5)
• Stopwatch
• Heatproof mat

• Square of cardboard with a hole in
• A selection of insulating materials
• Scissors
• Elastic bands

Method

Activity 1: Comparing the Effectiveness of Different Materials as Insulators

Setup:

Place a 100ml beaker inside a 250ml beaker.
Boil water in a kettle.

Start Experiment:

Carefully pour 80ml of boiled water into the 100ml beaker.
Cover the 250ml beaker with a cardboard lid.
Insert a thermometer through a hole in the lid so it sits in the water in the 100ml beaker.

Recording Temperature:

Record the starting temperature of the water.
Start the stopwatch.
Measure and record the temperature every 3 minutes over a 15-minute period in a suitable table.

Repeat with Insulating Materials:

Add different insulating materials between the two beakers.
Ensure to use 80ml of water each time.
Repeat the temperature measurements for each insulating material.

Results:

Plot the results on a graph to create a cooling curve for each material.
Analyse: Determine which material was the best insulator and explain why based on the graph.

Activity 2: Investigating How Thickness of Material Affects Heat Insulation

Setup:

Take a 100ml beaker.
Wrap the sides of the beaker in one layer of insulating material (leave the base bare).
Use elastic bands to secure the wrapping.
Boil water in a kettle.

Start Experiment:

Carefully pour 80ml of boiled water into the 100ml beaker.
Cover the beaker with a cardboard lid.
Insert the thermometer through a hole in the lid so it sits in the water.

Recording Temperature:

Record the starting temperature of the water.
Start the stopwatch.
Measure and record the temperature every 3 minutes over a 15-minute period in a suitable table.

Repeat with Additional Layers:

Add an increasing number of layers of the same insulating material to the beaker for each repetition.
Record the temperatures as before for each thickness level.

Results:

Plot the results on a graph to show the cooling curve for each thickness level.
Analyse: Identify how the thickness of insulation impacts heat retention based on the graph.

Technician tips

• Care should always be taken when dispensing boiled water from the kettle.
• Lids for the beakers could be pre-made with a hole for the thermometer to save time and prevent thermometer breakages.
• Students should use the same ‘amount’ of insulating materials during the first activity to control this variable.
• This required practical could be split over a couple of laboratory sessions allowing for equipment cooling.