Heat energy transfer is the process by which heat energy is exchanged between bodies or parts of the body at different temperatures. Heat energy is generally transferred by convection, radiation, or conduction. Conduction is the transferring of heat energy through any kind of material. Some materials are good conductors and some are bad conductors. For example, metals are good conductors. But wood is a bad conductor. This is because wood can absorb which separates the atoms further apart. Bad conductors are called good insulators.
People use wooden spoons in cooking, because heat energy cannot travel through the wooden spoon very easily. Metals are good conductors because the atoms are structured in a way that atoms can vibrate one another easily. Kinetic energy is transferred to cooler parts of the metal by free electrons as they diffuse through the metal, colliding with ions and other electrons. This happens to copper when it is heated at end. Liquids are not so good conductors as solids because the atoms are constantly moving around so the atoms do not vibrate one another as well.
There are also fewer atoms in liquids. For example Mercury. Gases are good insulators because there are a few atoms and the atoms are spread over a vast area which makes the process of vibration very difficult. Convection is the transferring of heat energy in liquids and gas. There are 5 steps to the way in which convection works. They are:- 1. Firstly, air warms up and becomes less dense. 2. Then, warm air rises. 3. Later, the air cools and becomes denser. 4. After, this denser, cooler air now sinks. 5. Finally, this cooler air now replaces the air which is rising.
This is the how heat energy moves in convection. Radiation is the transferring of heat energy by waves with no particles being involved. Hot objects send out mainly infrared radiation, and the hotter the object, the energy it radiates. How much radiation is given out or taken in by an object depends on its surface In the experiment, we going to test how fast heat energy is lost through a steel can. Before proceeding with the experiment we must find out where heat energy is being lost in the can. If we do this then we can prevent every section of losing heat energy. 1.
Heat energy is being lost by the side and bottom of the can by conduction because the energy from the water vibrates the molecules in the metal can. 2. Heat energy is being lost from the gap of the lid by convection because the energy in the water heats the air molecules which expands and rise but then cools and the heat energy is released into the air. 3. Heat energy is being lost by the side of the can by conduction and convection because the heat energy is being passed through the steel can, then through the bubble wrap and then through the air in the bubble wrap.
Finally the heat energy is then conducted through the other end of the bubble wrap. 4. Heat energy is being lost in the space between the lid and the water by convection because heat energy in air is being warmed up, then cooled and finally the air sinks. Unfortunately, we cannot stop conduction or convection because heat energy can escape in one way or another. So we cannot eliminate any of these heat energy losing problems. We can only put a material around the can to slow down the process of conduction. If we had a solution of stopping heat energy from traveling then there would not be any point of doing this experiment.
We shall be using one type of material but in two sizes. We shall be using bubble wrap. One bubble wrap will have big bubbles on it and the other will have small bubbles on it. What will happen to the heat energy is that it will escape from the sides and the bottom of the can and then through the bubble wrap. The bubble wrap will be a better insulator depending on its size. I think the big bubble wrap will be a better insulator than the small bubble wrap because the big bubble wrap has a gas in its bubbles and this makes heat energy hard to escape, as there are fewer atoms in gases than solids and liquids.
Heat energy takes longer to escape in gases than solids and liquids because the atoms in a gas are far apart so heat energy cannot vibrate an atom to another. Prediction From my research, I predict that the big bubble wrap will be a better insulator than the small bubble wrap because there is a lot gas in each bubble preventing heat energy from escaping so easily. I think the plastic bag will not be as good of an insulator as the bubble wrap because the plastic bag will be very close to the steel can. This will let heat energy just go through the steel can and the plastic bag. PLAN.