Page 47 - Science Course 1 (Book 2)

Mo8-L2a: How is Thermal Energy Transferred?

When you put a warm glass of water in a cold Heat Transfer
refrigerator, thermal energy is transferred
Conduction is the transfer of thermal energy by
Thermal energy moves collisions between particles in matter.
from the warm water to the
cool air by collision of the Radiation is the transfer of thermal energy by
particles.
electromagnetic waves.

Convection is the transfer of thermal energy by the
movement of the particles from one part of a
material to another.

Water Glass Air

• Particles in the water hit particles in the glass and
cause the glass particles to vibrate faster -
average kinetic energy (temperature) of the glass
increases.
• When the cool air particles hit the warm glass
particles hit the warm glass particles, the air
particles move faster after the collision. The
average kinetic energy (temperature) of the air
increases.

The movement of thermal energy from a region of Conduction, radiation, and convection are ways in
higher temperature to a region of lower temperature which thermal energy is transferred.
is called heat.
Thermal energy is transferred out
of hot water by radiation and
conduction.

When the temperatures of materials that are in
contact are the same, the materials are said to be in
thermal equilibrium.

Thermal energy Cycles of rising and
from the burner is sinking water transfer
transferred into thermal energy
water by conduction throughout water by
convection.

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