GCSE Physics Required Practical: Investigating Thermal Insulators

Key Stage 4

Meaning

Investigate the effectiveness of different thermal insulators on reducing an energy transfer by heating.

Experiment

Variables

Independent Variable: Insulating material.

Dependent Variable: The temperature decrease of water after a given time.

Control Variables: The volume of water used. The initial temperature of the water. The time taken between measurements. Thickness of the insulating material.

Method

A diagram of the apparatus used in an experiment to compare the effectiveness of different thermal insulators.

1. Measure 100ml of hot water (around 50°C) using a measuring cylinder.
2. Fill a can with hot water
3. Place a thermometer in the water and wait until the temperature reaches 40°C.
4. Begin a stopwatch when the temperature is 40°C then read the temperature every 30 seconds for 5 minutes.
5. Repeat steps 1-3 with a can covered each type of insulating material.
6. Plot a graph with temperature on the y-axis and time on the x-axis plotting the results for each insulating material on the same graph.

Improving Accuracy

Place the cans on a heatproof mat to reduce the thermal energy lost to the table surface by conduction.

Place a lid over the cans to reduce the thermal energy lost to the air by evaporation.

Complete the experiments with different insulators simultaneously so that a change in the temperature of the laboratory does not affect the results.

Place the measuring cylinder on a flat, level surface and read it from eye level to get an accurate reading of the volume of water.

A diagram including apparatus used improve the accuracy of an experiment to compare the effectiveness of different thermal insulators.

Improving Precision

Use a thermometer with a higher resolution.

Use a data logger rather than a thermometer.