Name
Date
Class
Lesson Outline
LESSON 1
Thermal Energy, Temperature, and Heat
A. Kinetic and Potential Energy
1. Any moving object has
energy.
2. The energy that is stored due to the interactions between objects or particles is
called
energy.
3. A moving soccer ball that has been kicked into the air has kinetic energy
and
energy; together they make up the
energy of the ball.
B. What is thermal energy?
1. The
that make up matter have kinetic energy and
potential energy.
2. The sum of the kinetic energy and the potential energy in the particles that make
up an object is called
energy.
3. Thermal energy describes the
of the particles in solids,
liquids, and gases.
C. What is temperature?
energy.
2. The average kinetic energy of the particles that make up a material is the
of the material.
a. A material with a(n)
temperature has particles that
have a greater average kinetic energy than a material with a(n)
temperature.
b. Particles whose average kinetic energy is large are moving at a(n)
average speed than particles whose average kinetic
energy is smaller.
3. Two materials can have the same temperature but different
energy. For example, ice and water have the
same average kinetic energy, but liquid water has
thermal energy because its particles have greater potential energy than those of ice.
10
C354_008_014_CRF_L1_892510.indd 10
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
1. Scientists define temperature in terms of
Thermal Energy
3/4/10 4:11:27 PM
Name
Date
Class
Lesson Outline continued
4. A(n)
is used to measure temperature.
a. A(n)
thermometer has a liquid that
and rises in a(n)
tube
when its temperature goes up; the liquid
drops when the temperature goes down.
and its level
b. A(n)
thermometer measures the resistance in an
electronic circuit and converts this measurement into
a(n)
.
5. Scientists around the world use the
scale.
a. Water freezes at
at
ºC and boils
ºC.
b. Scientists also used the Kelvin scale; water freezes at
and boils at
K
K.
c. The lowest possible temperature for any material is called
zero and is
K; at this
temperature the particles in a material would not be moving and would have no
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
energy.
D. What is heat?
1.
is the movement of thermal energy from a warmer
object to a(n)
2. All objects have
object.
energy, but heating occurs only when
energy is transferred from one object to another object.
a. The rate at which heating occurs depends on the difference in
between two objects; the greater the difference, the
heat is transferred.
b. Heating continues until all substances that are in
have reached the same
Thermal Energy
C354_008_014_CRF_L1_892510.indd 11
.
11
3/4/10 4:11:28 PM
Name
Date
Class
Lesson Outline
LESSON 2
Thermal Energy Transfers
A. How is thermal energy transferred?
1. A car that has been outside on a sunny summer day will be
inside.
2. Thermal energy can be
from one object to another by
, conduction, and convection.
B. Radiation
1.
is the transfer of thermal energy from one material to
another by electromagnetic waves.
2. All objects, even ice cubes, radiate
energy.
3. The only way for thermal energy to travel from the
to
Earth is through radiation; that is because radiation is the only way for thermal
energy to travel through the
4.
of empty space.
occurs in solids, liquids, and gases.
C. Conduction
1. When particles that have different kinetic energies
, the
kinetic energy transfer energy to
particles that have
kinetic energy; in this way, the
average kinetic energy, or
, of the materials changes.
a. Because kinetic energy is being transferred,
energy is
also being transferred.
b.
is the transfer of thermal energy between materials
because of collisions between the particles.
c. Conduction does not stop until the
energy of all the
particles that are in contact is
.
2. A material through which thermal energy flows easily is called
a(n)
not flow easily is called a(n)
a.
; a material through which thermal energy does
.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
particles that have
are good thermal conductors because they have
that move easily, so they often collide with other
particles and transfer
30
C354_028_034_CRF_L2_892510.indd 30
energy easily.
Thermal Energy
3/4/10 4:15:30 PM
Name
Date
Class
Lesson Outline continued
b.
are good thermal insulators because their electrons
do not
easily, so compared with thermal
conductors, few
of insulators.
3.
occur between electrons and atoms
is the amount of thermal energy it takes to increase the
temperature of 1 kg of a material by 1ºC.
a. Thermal
have a(n)
specific heat compared with thermal
low
, which have a
.
b. Water has a(n)
specific heat, which makes this liquid
good for
.
D. Thermal Expansion and Contraction
1. An increase in a material’s volume when the temperature is increased is
called
; this occurs because particles spread out as their
energy increases.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
2. A decrease in a material’s volume when the temperature is decreased is called
; this occurs because
closer together as their kinetic energy decreases.
get
E. Convection
1. The transfer of thermal energy by the movement of particles from one part of a
material to another is called
; convection occurs in
—liquids and gases.
2. Convection occurs, in part, because of differences in
due to thermal
parts of the material.
,
and thermal contraction in different
3. The movement of fluids up and down in a cycle because of convection is called a(n)
; these
cause patterns in
Earth’s climate.
Thermal Energy
C354_028_034_CRF_L2_892510.indd 31
31
3/4/10 4:15:31 PM
Name
Date
Class
Lesson Outline
LESSON 3
Using Thermal Energy
A. Thermal Energy Transformations
1. People can convert many forms of energy such as mechanical energy or chemical
energy into
energy; we can also convert thermal energy
into other
of energy such as mechanical energy.
2. Although energy can be transformed from one kind to another,
cannot be created or destroyed.
B. Heating Appliances
1.
are devices that convert electric energy into thermal
energy; some examples are clothes irons, and coffee makers.
2.
devices such as cell phones and computers also get hot
when they are in use; however, the
produce does not serve a useful purpose.
energy they
C. Thermostats
1. A device that regulates the temperature of a system is called a(n)
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
.
2. A thermostat has a
coil made of two types of metals
that
and contract at different rates; the coil curls and
uncurls, depending on the air
, to move a switch that
controls a(n)
.
D. Refrigerators
1. A(n)
is a device that uses electric energy to pump
thermal energy from a cooler location to a warmer location.
2. A(n)
, which is a fluid, flows through pipes that
surround the compartments of the refrigerator;
energy
is transferred from the inside of the refrigerator to the coolant, which is why the
refrigerator stays
.
3. A refrigerator uses
energy to move the
through the refrigerator pipes.
a. Starting as a liquid, the coolant passes through a(n)
changes into a gas, and becomes
Thermal Energy
C354_045_051_CRF_L3_892510.indd 47
,
.
47
3/4/10 4:27:48 PM
Name
Date
Class
Lesson Outline continued
b. The coolant removes the
energy from the inside of
the refrigerator, so the refrigerator cools off.
c. In the bottom of the refrigerator, there is a(n)
that
forces the coolant into a smaller space, which increases the
energy of the coolant.
d. The
releases thermal energy into the
around the refrigerator.
e. This change causes the
to become a liquid, and then
the cooling cycle begins again.
E. Heat Engines
1. A machine that converts thermal energy into mechanical energy is a(n)
.
2. A(n)
engine, such as those found in moving vehicles
and lawn
, converts thermal energy into
energy.
a. In a car engine, a spark ignites a fuel-air mixture, which
b. In an automobile engine, only about
percent of the
energy of the fuel (gasoline) gets converted into
energy; the rest become heat, which causes the car’s
to become hot.
48
C354_045_051_CRF_L3_892510.indd 48
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
and pushes a piston down; this motion turns the
crankshaft—the mechanical energy that moves the car.
Thermal Energy
3/4/10 4:27:49 PM