Finding the best Insulator
There are several factors which effect heat loss in a liquid for example the material used for insulation. This would be measured using a thermometer in a covered cup containing a hot liquid. Another factor which affects heat loss is the thickness of the material, so instead of having the type of material as the independent variable you could have the thickness. In my experiment the independent variable will be the thickness of bubble wrap and the dependent variable will be the amount of heat loss which I will measure using a thermometer. To ensure my experiment is valid my controlled variables will be the cup type, the volume of liquid, the initial temperature of the liquid, the type of liquid, the thermometer and the stopwatch. This will also ensure that this investigation is a fair test.
Energy transfer by conduction usually occurs in solids. This is when the atoms start to heat up and the heat energy is transferred into kinetic energy as they start to vibrate more. This then causes the rest of the particles to vibrate eventually heating up the whole object.  
To prevent heat escaping through the convection current I will place a seal on top of each cup. This then allows the atoms that make up the cup to vibrate because...