Transcript HEAT 11.2 Chapter Eleven: Heat 11.1 Heat 11.2 Heat Transfer Chapter 11.2 Learning Goals Compare and contrast various methods of heat transfer. Differentiate between thermal conductors.

HEAT 11.2
Chapter Eleven: Heat
11.1 Heat
11.2 Heat Transfer
Chapter 11.2 Learning Goals
Compare and contrast various
methods of heat transfer.
Differentiate between thermal
conductors and thermal
insulators.
Explain what it means when
objects are in thermal equilibrium.
Investigation 11B
The Specific Heat of a Metal
Key Question:
What is the identity of an unknown metal
sample?
11.2 Heat transfer
 Thermal energy flows from higher
temperature to lower temperature.
This process is called heat
transfer.
 There are three ways heat flows:
 heat conduction,
 convection, and
 thermal radiation.
11.2 Heat transfer
Heat conduction is the
transfer of heat by the
direct contact of
particles of matter.
Conduction occurs
between two materials
at different
temperatures when
Where is the heat energy they are touching each
conducted to and from in other.
this system?
11.2 Heat transfer
Thermal equilibrium occurs when two
bodies have the same temperature.
No heat flows in thermal equilibrium
because the temperature is the same
in the two materials.
11.2 Thermal conductors and
insulators
Materials that conduct
heat easily are called
thermal conductors
and those that
conduct heat poorly
are called thermal
insulators.
Is a down coat a
conductor or an
insulator?
11.2 Convection
Convection is the transfer of heat through
the motion of matter such as air and water.
The hot water at the bottom of the pot rises
to the top and replaces the cold water.
11.2 Convection
Convection is mainly what distributes
heat throughout a room.
11.2 Thermal radiation
Heat from the Sun is
transferred to Earth by
thermal radiation.
All the energy the Earth
receives from the Sun
comes from thermal
radiation.
The higher the
temperature of an
object, the more
thermal radiation it
emits.
11.2 Thermal radiation
Thermal radiation is also
absorbed by objects.
The amount of thermal
radiation absorbed
depends on the surface of
a material.
Dark surfaces absorb most
of the thermal radiation
they receive.
Silver or mirrored surfaces
reflect thermal radiation.
11.2 Heat transfer, winds, and
currents
A thermal is a convection
current in the
atmosphere.
When a surface, like a
road absorbs solar
radiation, it emits
energy as heat.
The warmed air
molecules gain kinetic
energy and rise.
Colder air is forced
aside and sinks.
11.2 Thermal radiation
There are giant
convection currents in
Earth’s atmosphere.
The global wind
patterns and Earth’s
rotation also cause
surface ocean currents
to move in large
circular patterns.
Investigation 11C
Mass Determination
Key Question:
Can the mass of an object
be determined without
the use of a balance?
Needed: Efficient Buildings
“Green” building design is the term
used to describe architecture that is
energy-efficient and environmentally
friendly.