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HEAT! HEAT! HEAT!
MASTER TEACHER Lucinda Munoz
GRADES 3-5
OVERVIEW
In this lesson and its extensions, students will learn the
relationship between molecular movement and heat; see how different substances
react in the presence or absence of heat; and finally compare the different
methods by which heat is transferred. The students will conduct their own
experiments with teacher supervision using beakers, water, candles, light bulbs,
rice, heat sources to who they understand convection, conduction and radiation.
ITV SERIES
Bill Nye the Science Guy #130 Heat
LEARNING OBJECTIVES
Students will be able to:
*describe the relationship between molecular movement and heat
*explain how different substances react in the presence of
absence of heat
*compare different methods by which heat is transferred
MATERIALS
"Heat Transferred by Radiation" Activity 1
1 electric lamp with light bulb
"Demonstrating Convection Currents" Activity 2
1 empty ink bottle with a cork stopper
2 glass tubes from a medicine dropper
1 small glass tube
large clear glass bowl
2 cups very cold water
2 cups very hot water
ink or food coloring
"Conduction of Heat Along Metal" Activity 3
1 metal rod or large wire (About 12 inches long) of copper,
brass or aluminum rod
6 or 8 thumb tacks
1 candle
matches
heat protective gloves
Post Viewing Activity 4
(per group of 4 students)
1 quarter
1 an old hankerchief
a candle or a match
Post Viewing Activity 5
(per group of 4 students)
1 hot plate
2/3 cup of rice
1 clear bowl that can be placed on heat
2 cups of water
Post Viewing Activity 6
(per group of 4 students)
1 magnifying glass
1/4 sheet of tissue paper
1 glass bowl
sunlight
fire extinguisher
VOCABULARY
Heat - the energy of moving molecules
Heat energy - makes molecules move and vibrate
Conduction - process of heat movement through a solid
Convection - heat traveling through a gas or liquid
Radiation - heat traveling through waves of infrared light which
strikes and excites molecules of matter
Molecules - cluster of atoms
Infrared light - electromagnetic radiation whose wavelengths are
longer than those of visible light but shorter than those of radio waves
PRE-VIEWING ACTIVITIES
Divide the class into groups of 4 students. Have 1 table
as a head table for teacher demonstrations. The purpose of the
demonstrations is to wet the students' interest in the subject of heat not
answer their questions, yet. As a focus, introduce activity 1, "Heat
Transferred by Radiation." Set the lamp on your demonstration table and ask
for a volunteer student to assist with the activity. With the lamp off,
hold your hand, palm up, two or three inches from the light bulb. Now turn on
the lamp. You should feel the heat almost as soon as the bulb lights. The heat
travels by waves of infrared light, that is radiation. The student should
feel it almost instantly. When heat travels by radiation it can even
travel across the vacuum in space. Ask students, "What do you feel when you
put your hands close to the light bulb?" (hands are getting hot) Asks,
"Where do you think the heat is coming from?" (the light bulb off the
lamp) Lead students to consider that the heat is coming from radiation.
Next introduce activity 2, "Demonstrating Convection
Currents" Make two holes in the cork stopper the size of two medicine
dropper tubes. The medicine dropper tube should have the small end up and the
other end flush with the bottom side of the cork. The small end should stick up
past the cork nearly two inches. The other tube will have one end flush with the
top of the cork and extend nearly to the bottom of the ink bottle. Fill a bowl
with very cold water. Color some very hot water with the ink or food-coloring
and pour it into the ink bottle. Press the stopper in place with the dropper
tube sticking up. Wipe off any outside water and quickly place it in the bowl of
cold water. A "Volcano" will immediately start to erupt. The heavy,
cold water will press into the tube going to the bottom of the bottle. This
pushes the lighter hot water up and out the dropper tube toward the surface.
This experiment visually demonstrates convection currents. Ask, "What is
happening to the water in the ink bottle?" (The water from the ink bottle
is coming out of the bottle and mixing with the water in the bowl.) Ask,
"Why do you think this is happening?" (accept all answers from
the students) Tell students it is because of convection and they will learn
about this phenomena when they view the video.
Last introduce Activity 3, "Conduction of Heat Along
Metal." Tell the students that they will see some magic. Prior to the
class period make sure that you have prepared the metal rod with the tacks so
the students don't see the process. Only allow the students to view you
placing heat on the rod. Attach 6 to 8 tacks to the metal bar with melted
wax from a candle. Position the tacks about an inch apart beginning at one end
of the rod. Be sure to wear protective gloves because the wax is hot and can
burn. When demonstrating the experiment for the students, holding the rod
with protective gloves place the end of the rod near the first tack over the
candle flame. Holding the rod in the same place over the flame, notice how the
tacks begin to drop from the rod. This shows that heat moves along the rod by
conduction. Conduction in physics is a form of energy, such as electricity and
heat that travels along a material from one molecule to another. As they watch
the rod the tacks will begin to fall and you will ask "What is happening to
the tacks?" (they are falling off the rod) "Why is this
happening?" (Accept al answers) Explain that this is happening because of
conduction.
All this magic in the three activities happens because heat
transfer by radiation, convection, and conduction. Give students a plain white
sheet of paper and have them hot do fold it into 3 equal parts. Label one part
conduction, one part convection and the last one radiation. Have each
student write down everything they know about each area of heat. Explain to them
that it is only a sponge activity to see how much knowledge they have about heat
already. Allow about three minutes for this activity. Have them draw a
straight line under the information they just finished writing. As they view the
video tell them to take notes on any new information they learn pertaining
to heat. At the end of the video, review all concepts. They can add any new
notes.
FOCUS FOR VIEWING
To give students a specific responsibility while viewing the
video, ask them to listen very carefully and take notes on the different
types of heat transfer. Have students listen for what moving molecules
have to do with heat. As they watch the video they will learn more about heat
transfer that was demonstrated in the beginning activities.
VIEWING ACTIVITIES
Begin the video at the very beginning where Bill is showing 2
iron rods, one hot and one cold and he says, "It's all about heat."
Fast forward past the song "Bill Nye". Resume the tape with
visual of the lab door. Have the students listen for Bill's explanation of
heat.
Pause the video where Bill licks the ice. Ask, "What
does Bill say heat is?"(energy, does work, makes engines run and affects
molecules) Resume the video and ask students to listen to Bill as he
explains how heat moves around the universe in 3 ways.
Pause the video right after Bill puts the flame out on the
marshmallow and he lists the types of heat; conduction, convection, and
radiation. Ask, "What is the griddle doing?" (providing heat for the
batter to cook and make pancakes) "This is an Example of what type of
heat transfer?" (conduction) "What did he use as an example of
convection?" (steam cooking the potatoes) "What was the example of
radiation?"(the fire cooking the marshmallows) Resume the video and
have students listen to the 3 students debate. Have students listen for
the main points each one defending.
Pause when the debate ends. Ask, "What does Ray Deation
say is the best heat?" (one that radiates from the sun) "What type of
heat does Connie Vection defend as the best?" (one that moves warm air up,
for example, fire or tropical breeze) "Conrad Duction defends his opinion.
What type of heat does he claim is best?" (best heat is conducted
from one thing to another, for example, metal spoon in a bowl of hot soup,
gets hot.) Resume the video and ask students to listen to Bill as he explains
how heat is everywhere.
Pause video where he throws the snowball. Ask, "Does
everything have heat?" (anything with molecules has heat) Resume and have
students listen to the Big Sweaty Guy explain how he has mass and how he has to
move it around.
Pause when he says, "Hot! Hot! Hot!" Ask,
"What happens to the heat in this person's body?" (he is big and
therefore has more mass to moves around) Fast forward to where Bill is opening
the door to the microwave to take the cup of soup out. Resume. Have students
listen to the explanation of convection using the cup of soup.
Pause where Bill says, "And this is soup." Ask,
"How is he cooling the soup?"(moving air) "What is type of
heat transfer called?"(convection from an old word meaning carry with, The
air molecules are carrying heat with them) Say, "Bill goes on to explain 2
types of convection. Listen for what are they. Resume.
Pause the video after Bill makes his explanation. Ask,
"What were the 2 types of convection?" (forced convection and natural
convection) "What is forced convection?"(when air is forced over the
heated matter example the blowing air over hot soup or heated coils are
considered forced convection) "What is natural convection?" (when
molecules begin moving around and around and further apart, example turning on a
burner to heat water Cooler molecules take the place of warmer molecules.)
Resume the video and listen as Bill's explanation of convection 1 more time.
Pause when the words Way Cool Scientists appear on the
screen. Review forced and natural convection?" Fast forward to where
Bill is sitting in front of the fire in the fireplace. Resume the video.
Have students listen as Bill explains radiated heat.
Pause when the girl puts a blanket on his back. Ask,
"What is the fire doing?" (radiating heat) "What is heat
radiation?"(It is made up of waves just like the light.) "What happens
to waves above the fire?"(rise up like convection) Fast forward to the
frame where Hot Treats begins. Resume the video and listen to the explanation of
heat in the kitchen.
Pause where the 3 circles of Bill Nye are seen. Say,
"Vivian Cupcakes explains heat conduction to us. How does the brownie
batter cook?"(through conduction, the heating element heats the oven, the
oven heats the metal pan and the pan cooks the batter in it) "What is the
difference between cooking in the metal pan and a glass pan?" (Metal is not
clear. So infrared heat can radiate through it. The pan reflects the heat in
order to bake the cookies. It take longer to cook in a metal pan. A glass
pan is clear and the infrared light radiates right through the pan and bakes the
brownies quicker.) Fast forward and resume the video where the 2 girls are back
to back. Have the students listen to the song of Heat.
Stop the video when Bill reviews the 3 processes of
transferring heat. Ask "What are the 3 processes of Heat
transfer?"(convection, conduction, and radiation) Review the video with the
students and recall the processes and the examples of each.
POST VIEWING ACTIVITIES
Say, "Remember what you just saw. What process was observed
as the pancakes were being cooked in the video?" (conduction)
"What examples of radiation were observed?" (cooking a marshmallow and
baking cookies) "Give an example of the process of
convection." (steam cooking potatoes) Ask several questions over the
3 processes of heat transfer and have the students review the notes they took as
they viewed the video.
It is now time for the students to begin their own activities
or experiments.
Post Viewing Activity 4
Materials-
coin (quarter or half dollar)
old handkerchief,
small candles or a match
Twist the handkerchief around the coin so that a single layer of
the cloth is stretched tightly across the flat side of the coin. Hold this flat
side over the flame of the candle for a few seconds. The cloth will not burn.
This is because the metal of the coin is a good conductor and it conducts heat
away from the cloth, keeping the temperature of the cloth below its burning
point. This shows heat transference by conduction.
Post Viewing Activity 5
Materials
hot plate
2/3 cup of rice
clear bowl that can be placed on heat
2 cups of water
Pour the 2 cups of water in the bowl and place on the burner.
Turn the hot plate on and wait for the water to begin boiling. Pour 2/3 cups of
rice and watch the rice as it turns over and over in the boiling water.
This shows the process of heat transference by convection.
Post Viewing Activity 6
Materials
magnifying glass
tissue paper
glass bowl
sunlight and
fire extinguisher
Place a small wad of tissue paper in the bottom of the bowl. The
bowl is to keep the fire from spreading. Hold the magnifying glass in the sun
and focus the rays to a fine point on intense heat, causing the paper to quickly
reach its kindling point. Be sure not to go off and leave your project or leave
the magnifying glass lying about, it could start a fire. This shows heat
transference by radiation.
ACTION PLAN
Have a person who works for an air conditioning company speak to
the students on how heat is transferred through the units.
A restaurant chef could come and advise the students on
cooking. The chef could explain how different pans and pots affect cooking
time.
Have the fire Marshall come and speak to the students about
fires and the radiation of the fire. Have him discuss the necessity of
being extremely careful with any form of fire.
EXTENSIONS
Reading
Read How Things Work-Heat, a book by Andrew Dunn. Discuss the
three types of heat transfer. Read Elmer in the Snow by David McKee. The
book explains how it is possible for all objects to have heat.
Construct a crossword puzzle using the vocabulary words
provided.
Art and Science
Determine which colors attract the most heat. Have
the students go out and put thermometers on different colors of construction
papers and record temperatures every 15 minutes for 1 hour.
SOCIAL STUDIES
Research different areas of the United States and find different
heating methods used in heating homes.
Updated: April 01, 2008
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