CH. 13 HEAT &
TEMPERATURE
NOTES
VIDEO CLIP 20 & 21
http://www.animatedscience.co.
uk/flv/
TEMPERATURE
is
a measure of the average kinetic
energy of all particles within an
object.
indicates
how warm or cold an
object is with regards to the
standard.
A
thermometer
is a device that
measures
temperature.
TEMPERATURE SCALES
 Fahrenheit
is a temperature scale used mostly in
the United States.
 Celsius is the temperature scale used mostly in
other countries and in science. Based on 0 C
being freezing point and 100 C being boiling
point, the difference between those two points is
divided up into 100 equal parts.
 Kelvin
scale is the temperature scale used by
scientists, where all of the numbers are positive.
It is based off the idea of absolute zero.
WHAT IS THE CELSIUS TO FAHRENHEIT
CONVERSION?
 F
= (1.8 x C) + 32.0
25 C to  F
  F = 77 (Did you get it right? Try this
one!)
 Convert
0 C to  F
  F = 32 (The freezing & melting point
of water)
 Convert
WHAT IS THE FAHRENHEIT TO CELSIUS
CONVERSION?
 C
= (F - 32.0)
1.8
 Convert your body temperature 98.6 F
to C .
 C = 37
 Convert
a warm Spring day’s
temperature of 78 F to C
 C = 26
WHAT IS THE CELSIUS TO KELVIN
CONVERSION?
K
= C + 273
 Convert
the temperature of a winter day
at the North Pole (- 40.0 C) to both
degrees Fahrenheit and Kelvin.
TRY IT USING THE USUAL SET UP
Unknown & Equations:
Known:
U:
F = ?
K=?
K:
C = 40.0
Substitute &
solve:
F = (1.8 x C) + F = (1.8 x
32.0
40.0C) + 32.0
K = C + 273
F = 40.0 F
K = 40.0 C +
273
K = 233 K
ABSOLUTE ZERO
is
the lowest possible temperature .
An object’s energy is zero. There is
no possible transfer of energy.
DEALING WITH TEMPERATURE WHEN
DOES AN ENERGY TRANSFER OCCUR?
The
feeling associated with
temperature difference results from
energy transfer.
Energy is transferred from a hotter
object to a cooler object.
Example
The
–Holding a piece of ice.
ice is at a lower temperature than
your hand, so the molecules of ice move
very slowly. Your hand’s molecules are
moving much faster than the ice because
it is at a higher temperature. As a result,
the molecules of your hand collide with
the ice molecules and energy is
transferred so the ice molecules start to
move faster causing the ice to melt.
WHEN IS THERE NO TRANSFER OF
ENERGY IN REGARDS TO TEMPERATURE?
If
both objects are the same
temperature there is no transfer of
energy AND
when
zero.
the temperature is at absolute
HEAT
is
the transfer of energy from the
particles of one object due to a
temperature difference between the
two objects.
Draw a picture to show what happens to the molecules
as thermal energy (heat) is added to the particles
More
Thermal
Energy
Draw a picture to show what happens to the molecules
as thermal energy (heat) is taken away from the
particles
Less
Thermal
Energy
http://www.middleschoolchemistry.com/multimedia/chapter2/lesson5#melt
ing_ice
http://www.middleschoolchemistry.com/multimedia/chapter2/lesson5#melt
ing_ice
Molecules begin to move faster as thermal energy is
added.
More
Thermal
Energy
Molecules begin to move slower as thermal energy is
taken away.
Less
Thermal
Energy
SECT. 10.2 ENERGY
TRANSFER NOTES
THREE METHODS OF ENERGY
TRANSFER …
1.
2.
3.
Conduction
Convection
Radiation
WHAT IS CONDUCTION?
It
is the transfer of energy as
heat between particles as they
collide within a substance or
between two objects in
contact.
http://www.animatedscience.
co.uk/flv/ (24)
TWO FACTORS INVOLVED IN
CONDUCTION
Has the direct contact of objects
or atoms.
2. Usually is an energy transfer
between solids
Example:
1.
 Leaving
a metal spoon in a pot of
soup cooking on the stove.
WHEN YOU HEAT A METAL STRIP AT ONE END, THE
HEAT TRAVELS TO THE OTHER END.
WHAT IS CONVECTION?
It
is the transfer of energy by
the movement of fluids with
different temperature.
http://www.animatedscience.
co.uk/flv/ (27)
HOW DOES CONVECTION MOVE?
It
is a result
from the
movement of
hotter fluids
to colder
fluids.
TWO TYPES OF FLUIDS
Gases
and
liquids.
CONVECTION CURRENT.
is
the flow of a fluid due to the
heated expansion followed by
cooling and contraction
Examples:
 Glowing
embers caught in the warmed
air above a campfire, or the movement
inside the earth for the plate tectonic
movement.
WATER MOVEMENT
Cools at the
surface
Cooler
water sinks
Convection
current
Hot water
rises
WHAT IS RADIATION?
Radiation
is the transfer of
energy by electromagnetic waves.
Examples:
 When
you stand by fire, your skin
absorbs the energy radiated by the
fire.
 http://www.animatedscience.co.u
k/flv/ (29)
How does heat energy get
from the Sun to the Earth?
?
There are no particles
between the Sun and the
Earth so it CANNOT travel
by conduction or by
convection.
RADIATION
HOW DOES RADIATION DIFFER
FROM CONDUCTION AND
CONVECTION?
It
does not involve or the
movement of matter (or physical
contact between objects). So it
can travel through a vacuum like
space.
HOW IS RADIATION LIKE
CONVECTION?
Radiation
is like convection in
that it can travel through fluids.
CONDUCTORS
are
materials through which energy
can easily be transferred as heat.
Examples - Some cooking pan,
copper, and silver.
In general metals are better than
nonmetals.
INSULATORS
are
materials that are poor
energy conductors.
Examples - Some insulators are
wood, foam, rubber, and
polystyrene