Transformation of Energy
Part 2: Heat Energy
Key Learning: Energy is all around us, comes in different
forms, and can change from one form to another.
Unit Essential Question: How does
energy move from one object to
another object?
Transformation of Energy
Part 2: Heat Energy
Concept: Heat Energy
Lesson Essential Questions:
1. How are heat energy and temperature
related?
2. What happens when an object gains or
loses heat?
3. How do radiation, conduction, and
You will be able to
answer these
questions by the
end of Part 1
convection transfer heat from one place to
another?
Vocabulary
Heat Energy
Temperature
Particle Model
Conduction
Convection
Radiation
You should already know what these
words mean. You will be able to use
them in your responses and
discussions throughout the unit
Transformation of Energy
Part 2: Heat Energy
Complete Warm Up #1: You’re riding your bicycle down
the street and have to slam on the breaks. You see that
you left a black tire mark on the sidewalk. What type of
energy transfer/transformation is this evidence of? How
do you know?
Transformation
TransformationofofEnergy
Energy
Part Part
2: The
2: flow
Heatof
Energy
Energy
A Quick Review of the Particle Model
Energy Decrease
Energy Increase
When energy is transferred to a substance (or is heated up, which is
the same thing), the particles become less dense, vibrate faster
(become more excited), and spread out. This is the case with all
substances. When a substance cools down or loses energy or energy is
transferred away, the opposite is true. The particles become less
excited, more dense, and their bonds become stronger.
Transformation of Energy
Part 2: Heat Energy
INVESTIGATION #3: Smoke Signals
TRANSFORMING KINETIC ENERGY INTO HEAT ENERGY
GOALS: In this investigation, you will …
• Observe what happens when large quantities of kinetic energy are
transformed into heat energy, and this heat energy is concentrated in one
part of an object.
• Recognize that forces are not energy, they are the mechanism by which
energy is transferred in a system
• Look at the role that forces play in the transfer of kinetic energy, and its
transformation into heat energy.
INVESTIGATION OVERVIEW: A synopsis of this lesson is as follows…
This is the first, and possibly the most dramatic investigation of the heat energy
component of the TOE unit. By illustrating the transfer and the transformation of
kinetic energy into heat energy, this investigation bridges the investigations of the
energy of large moving objects (balls, cups, bottles, etc.) and the investigations of the
kinetic energy of particles, the heat energy. Distinguishing between the organized
kinetic energy of the moving rope and the random kinetic energy of the particles of
the rope and wooden dowel is the primary goal of this investigation. This distinction is
made by looking at the different effects that both types of energy have on the
properties of the objects involved.
Transformation of Energy
Part 2: Heat Energy
This is what you’re set up should look like. Follow the procedure.
Reminder: do not use short quick pulls, use long, even pulls! Keep
the rope IN THE SAME SPOT ON THE DOWEL!
Transformation of Energy
Part 2: Heat Energy
Investigation Analysis
1. Why didn’t the cup show signs of heat energy transformation even though
our studies have led us to discover that all energy transfers and
transformations involve heat being transferred?
2. Use the Particle Model to explain why it is important to keep the rope
sliding across the same spot on the dowel if you expect the dowel and rope
to get hot enough to start burning.
3. How does kinetic energy transforming to heat energy affect the molecules of
an object or substance?
Transformation of Energy
Part 2: Heat Energy
Complete Summary #1: Rubbing your bare hands together creates
friction, transforming kinetic energy into heat energy. What is one way
you could reduce the friction so that you did not transform as much
kinetic energy into heat energy?
Try it out… Were you right, did you reduce the amount of heat energy?
Transformation of Energy
Part 2: Heat Energy
Homework Assignment #4
In the Transformation of Energy reading and
assignments…
Read pages 10-11 and complete
the assignment on page 12
Transformation of Energy
Part 2: Heat Energy
Complete Warm Up #2: Think of an example where an
increase in energy would cause the molecules of an object
to change. (You cannot use an ice cube or wood rod!)
Transformation of Energy
Part 2: Heat Energy
Investigation #4: Heat Energy and Temperature: THERE IS A DIFFERENCE!
GOALS: In this lab investigation, you will …
• Observe that there is a difference between the heat energy transferred to an object and
the change in temperature that results from this transfer of energy.
• Learn how the mass of a substance influences how much its temperature will change when
it receives heat energy.
• Learn that different substances respond differently when they absorb energy.
INVESTIGATION OVERVIEW: A synopsis of this lesson is as follows…
Tea candles will be introduced as sources of heat energy. We will assume that the tea candles
burn identically. We will also assume that each of the tea candles burns uniformly, so that it
produces the same amount of heat energy each minute it burns. The first step in the
investigation is to make an energy chain describing where the heat energy produced by the
candle comes from. Then the class will divide into five groups. Two groups will use candles to
‘heat up’ 100 grams of water, two other groups will ‘heat up’ 200 grams of water, and the
fifth group will ‘heat up’ 200 grams of sand. Groups that are working with 100 grams of water
will separate and use either 2 or 4 candles to ‘heat up’ their water. The groups working with
200 grams of water will divide up in the same way, and the group working with the sand will
use 4 candles. Each group will measure and record how the temperature of their substance
changes over a 6 minute period. The class will then share their results and look for patterns
in the results.
Transformation of Energy
Part 2: Heat Energy
Pick a Hypothesis…
Transformation of Energy
Part 2: Heat Energy
Here is the progression of how your set up will look.
Please follow the procedure and all safety rules,
especially since there will be hot wax and open flames.
100ml Water 100ml Water 200ml Water 200ml Water 200g Sand
2 candles
4 candles
2 candles
4 candles
4 candles
Initial
Temperature
1 minute
2 minutes
3 minutes
4 minutes
5 minutes
6 minutes
Change in Temp
Transformation of Energy
Part 2: Heat Energy
Transformation of Energy
Part 2: Heat Energy
Complete Summary #2: In the backyard of a house, there is a large pool,
a kiddie pool, and a sandbox. The sandbox and kiddie pool have the
same amount of substance. Which of the three will heat up quicker?
Explain your reasoning.
Transformation of Energy
Part 2: Heat Energy
Complete Warm Up #3: I have two cups of water. One is 10°C and the other
is 100°C. Draw what the particles look like in each cup.
10°C
100°C
Transformation of Energy
Part 2: Heat Energy
INVESTIGATION #5: Mixing and Melting
HEAT ENERGY & TEMPERATURE II
GOALS: In this investigation, you will …
• Predict and observe what happens to the final temperature of water when known amounts of hot
water are mixed with known amounts of cold water.
• Use the data you collect and the Particle Model to build a better understanding of heat energy and
temperature.
• Learn about and describe what is meant by thermal equilibrium.
• Study the melting process by melting ice.
INVESTIGATION OVERVIEW: A synopsis of this lesson is as follows…
The investigation begins with the review of heat energy and temperature changes as viewed through
the Particle Model. In this investigation, two samples of water having different initial temperatures
will be mixed together, and we will make predictions about the outcome of the mixing process. In the
previous investigation, heat energy was added to the samples of water by burning candles. Here, there
are no burning candles. All of the heat energy is added to the water samples before they are mixed.
We will see that the final temperature of the mixed samples depends on their initial temperatures and
their masses. The concept of thermal equilibrium will be introduced to answer the question “When is
the mixing done?” Finally, we will mix hot water and ice to see if the solid water (ice) at 0°C behaves
differently from liquid water at 0°C.
Transformation of Energy
Part 2: Heat Energy
Investigation Analysis
1. How would you respond to the following argument made by one of your
classmates? “When the hot water was mixed into the cold water, the
cold in the cold water canceled the heat in the hot water, and the
mixture ended up warm.”
2. Rubbing alcohol has a lower boiling temperature than water (meaning it
changes phases at a cooler temperature). If you place rubbing alcohol or
hand sanitizer on your bare arm, it will quickly evaporate and your skin
will feel cool. Why does your skin feel cool? Why can you easily smell
the alcohol?
Transformation of Energy
Part 2: Heat Energy
When a hot object and cold object
touch, how is heat energy transferred between the two
objects?
Complete Summary #3:
Transformation of Energy
Part 2: Heat Energy
Homework Assignment #5
In the Transformation of Energy reading and assignments…
Read page 13 and complete the
assignment on page 14
Transformation of Energy
Part 2: Heat Energy
Complete Warm Up #4: When cooking food on the stove using a pan,
the food heats up even though it does not touch the burner. How do
you explain this?
Transformation of Energy
Part 2: Heat Energy
Conduction is the transfer of heat through solids
or between two solids that are touching
Convection is the transfer of heat in liquids and
gases
Radiation is the transfer of heat through space
(no matter is needed for this transfer to occur)
1. An old-fashioned radiator heating up a room
2. Ice cooling down your hand
3. Boiling water by thrusting a red-hot
piece of iron into it
4. Heat from a fire
5. Hot air rising, cooling, and falling
6. Touching a stove and being burned
7. Heat from the sun warming your face
8. Heat from a lightbulb
9. Heat from anything else which is
warmer than its surroundings.
Transformation of Energy
Part 2: Heat Energy
CONDUCTION:
-Touching a stove and being burned
-Ice cooling down your hand
-Boiling water by thrusting a red-hot
piece of iron into it
CONVECTION:
-Hot air rising, cooling, and falling
(convection currents)
-An old-fashioned radiator (creates a
convection cell in a room by emitting
warm air at the top and drawing in cool
air at the bottom)
RADIATION:
-Heat from the sun warming your face
-Heat from a lightbulb
-Heat from a fire
-Heat from anything else which is
warmer than its surroundings
Transformation of Energy
Part 2: Heat Energy
Transformation of Energy
Part 2: Heat Energy
End of Part 2 Assessment
Directions:
In groups of 2 or 3…
You will be creating a poster to represent one of the methods of
heat energy transfer.
1. Make a rough draft of a picture to represent the three methods of
transfer and have Mr. Herlihy check it. You may not use words except
to title the poster.
2. Create your final poster
3. Make it colorful and interesting so it is not boring to look at