A Diagram To Show Conduction
Convection is also present in this experiment. In the beaker, there is a space between the top of the beaker where it is covered and where the water starts. Here there would be a convection current. A convection current is when air is heated, it then expands and floats upwards. Cooler air then moves into its place.
An Example of A Convection Current
The student’s hypothesis is wrong. Aluminium foil was actually the worst insulator in the experiment. I can understand why the student thought this because she says, “in hospitals, aluminium foil is used to cover people suffering from hypothermia”. From this, you would think that aluminium foil must be the best insulator. This is not true, but the aluminium foil does reflect the heat that the person already has back to s/he.
An Example of Aluminium Reflecting Heat
An Example of Radiation
There is empty space between us and the Sun. Nevertheless, we still get heat from the Sun. The energy travels as tiny waves of electromagnetic radiation. Sometimes, it is called heat radiation. Everything gives off some heat radiation. The hotter the object is, the more it radiates. Radiation can travel through solids, liquids, gases, and vacuums because it does not need particles, unlike convection and conduction.
Evaluation
The student could have made her investigation more reliable by doing the test more than once. Then the student could have taken an average of s/he results making them more accurate and reliable. Instead of using a thermometer, the student could use a temperature probe. A temperature probe is a metal rod, which measures the temperature of an object. The temperature probe is plugged into a computer where the temperature of an object is recorded constantly in a form of a graph. This will also make the students experiment more accurate and reliable. The student does not mention the thickness of the materials in the method. The student said that s/he used one layer of material only but, the materials are all different thicknesses therefore, different amounts of layers are needed for this experiment.
To improve this test the student could use a temperature probe. This would measure the temperature constantly, giving an accurate reading when the student chooses too. Also, doing the test more than once and then taking an average. This would make the experiment more accurate for when the student writes up the results of the experiment. Measuring the thickness of the materials of the insulators would also make the student’s experiment more reliable.
