hurumanu 4 (sciene)

Convection and conduction are both types of heat transfer where energy is passed from hot to cold.

When an object is heated up, the particles in it start moving faster as they gain energy.these particles also try to spread out as the gaps between particles get bigger. 

if an object is heated from one end, the particles can transfer heat along. This is conduction. 

some objects are good at passing on heat- these are called thermal conduction-

objects which are bad at passing thermal insulators. 

• conduction -  transferred through contact. 

• thermal insulators - do not pass on heat. 

• thermal conduction can pass on heat. 

1. curtains 

2. insulting-pink baits 

3. blankets 

4. polar fleece 

convection- non contact energy transfer, usually in liquid 

as heated particles expand and move faster they also rise up. As this occurs colder particles sink because they are more dense(as particles are closer together). 

this process continues eventually the whole liquid would get heated up.

this movement is called convection currents 

It can also be seen in air, as warmer air is less dense and rises. 

• convection-non contact heat transfer. hot stuff rises, cold stuff sinks.

tea bag rockets .

what happend to the tea bag? 

• the teabag was lit on fire and they spread out into the air because is was hot but when it was cold it came down.  

the marshmallow animation thingy-