Name _________________________________________
Section _____________ Week 11: October 21, 2008
Conduction, Convection, and Radiation
Student Performance Indicator:
Related pages in the textbook:
Key Points:
Predict the heat flow between objects
Chapter 4 Section 3 (4.3): pages 116-119
 Conduction is the process that moves energy from one
object to another when they are touching physically
 Convection is the process that transfers energy by the
movements of large numbers of particles in the same
direction within a liquid or gas
 Radiation is energy that travels as electromagnetic
waves.
I. Energy moves as heat in three ways (page 116)
a. Heat is the transfer of energy from objects at a _____________________ temperature to objects at
a ___________________ temperature.
b. How does energy get transferred from a warmer object to a cooler one?
1. _____________________________
2. _____________________________
3. _____________________________
II. Conduction (page 117: the first three paragraphs)
a. Conduction is the process that moves energy from one object to another when they are
________________________________________.
b. If you have ever __________________________________________________, you have experienced
conduction.
c. Conduction occurs any time that objects at ______________________ temperatures come into
contact.
d. The average kinetic energy of particles in the warmer object is great than of the particles in
the _____________________ object.
e. As long as the objects are in contact, conduction continues until the temperature of the
objects are _____________________.
f. Conduction can also occur within a ________________________________________.
g. In this case, energy is transferred from the ________________________ part of the object to the
______________________ part of the object.
h. Example: Suppose you put a metal spoon into a cup of hot cocoa.
i. Energy will be ___________________________ from the ________________ end of the spoon to
the ______________________ end until the temperature of the entire spoon is the
______________________.
III. Convection (page 118)
a. Energy can also be transferred through the _________________________________________________.
b. Convection is the process that transfers energy by the movement of large numbers of
______________________ in the ___________________________________ within a liquid or gas.
c. In most substances, as the kinetic energy of particles ______________________, the particles
____________________________ over a larger area. An increased distance between particles causes
a decrease in the _________________________ of the substance.
d. Convection occurs when a _______________________, denser mass of the gas or liquid replaces a
__________________________, less dense mass of the gas or liquid by pushing it upward.
e. Convection is a cycle in nature responsible for most ___________________ and ________________
_______________________.
f. Convection in air
1. Cooler, ____________________ air flows in underneath the _________________, less
dense air and pushes the warmer air upward.
2. When the air ________________, it becomes ______________ dense than the
____________________ air beneath it.
3. The cooled air sinks and moves under the warmer air.
g. Convection in liquids
1. Warm water that is ____________ dense than _________ water, so the warmer
water is pushed upward as the cooler, denser water moves underneath.
2. When the warm water that has been pushed up cools, its density
______________________.
3. This cycle continues when this more dense water sinks, pushing warmer
water up again.
IV. Radiation (page 119)
a. Radiation is energy that travels as _____________________________________________________________.
b. Examples of electromagnetic waves include:
1. ____________________________________
2. ____________________________________
3. ____________________________________
c. The ____________ is the most significant source of radiation that you experience on a daily
basis.
i. You can feel radiation as _____________ when radiation from the sun warms your skin.
ii. The radiation emitted from the sun strikes the particles in your body and transfers
___________________.
iii. The transfer of energy increases the movement of ___________________ in your skin,
which you detect as an increase in _________________________________.
iv. Of course, you are not the only object on Earth that absorbs the Suns’ radiation.
Everything, from air to concrete, absorbs radiation that increases particle motion
and produces an ____________________ in temperature.
d. When radiation is emitted from one object and then is absorbed by another, the result if
often a transfer of ___________________ through ______________.
e. Like both conduction and convection, radiation can transfer energy from ______________ to
____________________ objects.
f. *However, radiation differs from conduction and convection in a very significant way.
Radiation can travel through ___________________________________, as it does when it moves from
the Sun to the Earth.