Convection and Conduction are ways that things that can pass on heat energy.
When an object is heated up, the particles in it start moving faster as they get more energy. These particles also try to spread out as the gaps between particles get bigger. If they move faster and they touch another particles it passes on the heat to the other particles.
Conduction- transferring energy through contact . If something is good at passing on heat is is called a thermal conductor.
If something is a good thermal conductor it can pass on the heat. You need to get the heat from somewhere to pass it on eg. a jug can be a good conductor, it gets heated up by the heat underneath, another example is a stove top because it gets it's heat from the conductor from electricity and passes the heat to the food in the pan/pot.
if something is bad at passing on heat it is called an insulator/ objects which are bad at passing on heat are called thermal insulator.
Thermal Insulator - does not pass on heat. (bad conductor) eg. pink bats inside of the walls of your house and jackets are thermal insulators.
There is another way to pass on heat and that is called convection
Convection- non contact energy. can happened through air. eg. if a heater heats up the air the hot air rises and the cold air goes down and boiling water. Convection forms currents that move up and down- hot particles rise and cold particles sink.
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What happened with out tea bag rockets? (our tea bag rockets flew up to the roof as we lighted them)
- Our rockets showed convection. As the tea bag heats up the particles spread out, as the particles spread out they become less dense ( less compacted). If something is compacted it will be heavier. If particles are spread out it is less dense so it will become lighter. That is why our tea back rocket flew into the air. They spread out making them lighter so it goes up while it is up in the air it cools down and sinks.
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