conduction

CONDUCTION

DEFINATION: Conduction is the process of thermal energy without any flow of the material medium.

Thermal energy is transferred from a region of higher temp. to a lower temp. but the time interval that it is transferred varies on the type of medium being used.

thermal energy is transferred faster in a good conductor (eg. wood) but slower in a poorer conductor( insulator).

this reminds me of a joke. one day a conductor lost his baton hence uses a sword to conduct. during practice, a player was constanly playing out of tune and the conductor got very angry and threw the sword at the player. he killed the player and was sentence to death through a electric chair but survived. the law states that if a man is not dead by the electric chair after 3 times of shocking, he can be released. and one day, the conductor lost his baton again and the same thing happen and still survived the electric chair. Why is this so? it is because he was a bad conductor.



Heat travels up slowly through the wooden and plastic ladle and even faster through the metal ladle thus the metal ladle will feel heated faster compared to the wooden and plastic ladles.

Heat is transferred when molecules start to vibrate rapidly and bumping faster and faster into their slower"neighbors" causing them to speed up in turns . this process continues throughout the ladle ,the increase speed in vibration and therefore the heat is passed on to molecule to molecule or from atom to atom.

wood and plastic are bad conductors of heat
metal is a good conductor of heat :) conducts heat rapidly

why are metals good conductors?

Metal contains electrons that are not attracted to nucleus ,moving in a random motion. FREE ELECTRONS

Not only the atoms at the end of the ladle start to vibrate , the electrons also speed up and begin to move faster, colliding with the atoms more often and with more force.

Each time a free electron collides with an atom ,it causes that atom to vibrate a little faster.

The metals contain millions of those free electrons with collides with atoms and speed up the vibrations of atoms and the transfer of heat .

Thus non metals are bad conductors of heat while metals are better conductors of heat