Friday, February 4, 2011

Today in class we reviewed the homework," More matters". We discussed what experiments could be performed to see if heat can be added or removed from a system. Someone said we should measure a closed container of water's weight and place it on a stove and see if the weight increased.

In class, we performed a similar experiment. We lit a blade of metal. The metal weighed 7.9 grams before we lit it. After it was lit, the weight remained the same. This disproved Elmar's idea of heat which was it can be added or removed from a object.

By doing this experiment, we learned:

*Heat isn't a physical, if it was metal would've gotten heavier.*
*Heat is a process,it's the movement of particles.*

We defined conduction by stating it was the transfer of energy by touching. (particle to particle)
We defined convection by stating that it was the transfer of energy through fluids(ex.water,air,play-doh, jello,etc.)

Fluids- are not state, it's a classified combination of liquid or gas.

Mr.Finley asked us why the goo in the lava lamp moves?
Our answer was that the goo was heated up by the energy source.(light).

The exact process on how a lava lamp really works is :

energy source shoots out light waves ~ waves hit particles, particles move faster ~ particles spread out ~ substance expands ~ substance is less dense(particles are spread out in it),so it floats ~ floats to the top ~ substance is further away from energy source ~ energy (particles) transferred to environment which means substance has less energy ~ particles are moving slower ~ particles condense,(denser) so sink to bottom ~ cycle starts again because goo is closer to the energy source (light) again
AR (3rd)

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