Conduction Flashcards
What are free electrons?
Electrons that carry energy around the metal and give it to other electrons, ions
Only metals have free electrons
How are metals at conducting?
Metals are better conductors then non-metals
Heat carried by free electrons
Why is copper a better conductor than steel?
Denser
Particles are closer together
More free electrons to carry excess energy around the metal
Is water a good conductor of heat?
No
No free electrons
Particles far apart
What do we call a bad conductor?
Insulator
Why is air a good insulator?
Particles in air far apart
No free electrons
Robins fluff up during winter
Air is a very good insulator
Fluff up means air is trapped
Bird insulated
String vest keeps you warm.
Traps pockets of air
Insulated you
Shake a sleeping bag before using it.
Trap air in pockets
Insulates you while you sleep
Carpets feel warm in bare feet, ceramic tiles feel cold.
Between the strings of the carpet is trapped air
Insulates carpet so it is warmer
Saucepans have copper bases and wooden handles.
Copper conducts heat, heats up saucepan
What does not conduct heat so you don’t burn yourself
Copper has free electrons, wood does not
Gold conducts heat 80 times better than mercury
Gold is more free electrons than mercury
Heats up faster
Wear lots of thin layers instead of one thick layer.
Pockets of air between layers
Air insulates you
What is conduction?
When is transferred through solid
Heat is passed on by vibrations in the molecules
Vibrations bigger when solid has more energy
Why does metal feel warmer than wood?
Metal transfers heat faster to your hand then wood
