Page 30 - Digital Book Bilingual Perpindahan Kalor

Conduction

However, not all materials transfer heat in the same way. The rate at
which heat propagates in solid substances differs from one material to

another. Some materials transfer heat very easily, while others do so
with great difficulty. Materials that easily transfer heat are called
conductors, whereas materials that are difficult to transfer heat are

called insulators.

t h e r m a l i n s u l a t o r
t h e r m a l c o n d u c t o r
t h e r m a l c o n d u c t o r s s t h e r m a l i n s u l a t o r s s

Thermal conductors are materials Thermal insulators are materials
that allow heat energy to flow that do not transfer heat easily.

easily through them. In these This is because they lack free
materials, heat is transferred by electrons that can move and carry
vibrations of particles and the thermal energy. Materials such as

movement of free (delocalized) wood, plastic, and glass have
electrons. Metals such as silver, tightly bound electrons, so heat is

copper, and aluminium are good transferred slowly. As a result,
conductors because their free these materials are used to reduce

electrons can move easily and heat transfer.
carry energy, allowing heat to

spread quickly.

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