How to Do a Simple Heat Conduction Experiment

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How many of you parents are extremely comfortable with teaching science? And I mean extremely comfortable.

If you’re not, you’re not alone! I’m not much of a science buff myself. I got good grades in it as a kid, but I haven’t really ever been interested in it. (Except for astronomy. Astronomy is awesome.)

So when it comes to teaching science, I find it hard to get a good grasp of the concepts so I can teach them to my kids. And that’s why I was thrilled to get a chance to review a great science book and try some of the activities, including a simple heat conduction experiment!

Read on to see why I loved this book and to see one of the included hands-on activities!

Disclosure: I received this product in exchange for this post and I was compensated for my time. All opinions are my own and I was not required to post a positive review.

Science Concepts for the Non-Scientific Parent

As I mentioned earlier, I’m not super comfortable with science. And what’s worse – I’ve forgotten most of what I did learn in school. Fortunately, I’ve recently gotten a copy of the book Air Is Not Oxygen: Essential Science You Should Have Learned … But Probably Didn’t! and I have to say: It. Is. Incredible.

It’s a thorough overview of several scientific concepts, including light, heat, animal behaviors, and more. So it’s a good introduction or re-introduction to the same things you and I learned in school.

I had so many “Ohhhhh!” moments reading this book. For example, when Dr. Morelan talks about heat, he explains that you can generate heat through physical or chemical reactions. And for a physical reaction example, he tells you to rub your hands together (warming them) and then wave them in the air (cooling them).

Now did you ever think of that as friction or an example of how heat is generated? I didn’t!

And the book is written in a witty, conversational manner that just makes sense. I actually found my husband reading it later. That’s how good it is.

Simple Heat Conduction Experiment

After I read the section about how heat is generated with the kids, we tried one of the experiments in the book to observe heat conduction in action.

What is heat conduction? It’s how heat travels from one object to another. For example, when you touch something made of metal, it feels cold, right? Know why?

Because the metal is sucking the heat out of your body! For real! Just another thing I learned from Air is Not Oxygen. (Seriously, buy it now. You’ll be glad you did.)

It turns out that metal is an excellent heat conductor. And to test that statement, the book recommends experimenting by comparing to two other materials to see which one conducts heat the best. We took butter and spread it onto a plastic spoon, a metal spoon, and a pencil.

Then we stood all three up in a glass and added hot water.

And slowly but surely, the butter on the metal spoon began to soften.

We watched with bated breath…

Until it finally melted!

The butter on the pencil softened, but the butter on the plastic stayed fairly firm.

Yep. There’s no doubt that metal is the best conductor of the three. Science works!

This whole experiment took about half an hour. And most of that was spent in the observation phase. It was a really simple science experiment and a great way to “see” science in action.

And I finally understand what heat conduction is!

To brush up on science concepts and give your kids a chance to try a fun and simple heat conduction experiment, get your copy of Air is Not Oxygen from Amazon!

For more science fun, check out my It’s Science board on Pinterest!

And you can get even more ideas for teaching all kinds of homeschooling subjects, including science, in the book “The Big Book of Homeschool Ideas” from iHomeschool Network!

Comments

What a great experiment! That’s a new one for us. Can’t wait to try it! We are enjoying the Air Is Not Oxygen book, also. The projects are fun and the text cracks me up.

Abstract

Thermal Conductivity is an important material property in industry and daily situations like knowing what to choose in cookware or the proper clothing worn to leave the house. This property is described in units of Watts per meter Kelvin and at steady state can be calculated via a measurement of thermal resistance. Both Thermal Conductivity and Thermal Resistance will affect the amount of heat which passes through a system. In this experiment, a simple set-up will be employed to observe the change in heat flow.

Introduction

The goal of this experiment is to demonstrate the effect which varying thermal conductivities have on the heat flow through a given material. Ultimately this will provide a better understanding of both thermal conductivity and thermal resistance

Background Information and Equations

Background Information

Thermal Conductivity is a measure of a materials ability to transfer heat through itself and is one of the 3 variables in Thermal resistance. Thermal Resistance is analogous to Electrical Resistance in that it is inversely proportional to the flow of heat. In a laboratory setting, thermal resistance is calculated under specific circumstances allowing for thermal conductivity to then be derived from the obtained results.

Heat Flow Equation Q = ΔT / RΘ

• Q = Heat flow in Watts
• ΔT = Temperature difference in Degrees Celsius
• RΘ = Thermal Resistance (l / k ⋅ A)
• l = Length of a material in Meters
• k = Thermal conductivity constant in W/m-K
• A = Surface area in meters squared

This experiment will vary the bolded constant via different samples.

This experiment was designed to compare thermal conductivities thus surface area, length and temperature difference must remain the same in every test. One may use non-metals for this experiment however, may run the risk of lengthy testing time or potential incompletion. It is therefore suggested that metals be used. A listing of common metals may be found in the comparison section.

Materials

Procedure

1. 1. Obtain two beakers (similar or different size), fill one with water and place it on the hot plate.
   2. Place the other beaker on object of similar size to the hotplate as to make the lips of both beakers at the same height (or use a taller beaker)
   3. Bend all the wires 90° on both ends creating 50mm arms and ensure that 1m of straight wire is maintained
   4. Ensure that the bent end of the wire is immersed in the water
   5. Place all three wires of choice on the lips of both beakers as to connect both beakers

1. Use a marker to mark each wire every 200mm or if using candles, melt the bottom of each candle using some source of heat and place the candles at 200mm intervals along the wire
2. Heat the water using the hot plate for 15 minutes and then take temperature readings at each 200mm intervals

*shorter wires may be used for a faster experiment time if needed, simply make a measurement at every 1/5th of the wire*

Observation

There are two ways one can visualize the progression of the heat through the wires. Initially, one can observe the degree to which the candles melted at each 200mm interval. The wire with the highest thermal conductivity will have the greatest severity of melted candle, whereas; the wire with the lowest thermal conductivity will have the weakest severity of melted candles near the heat source. One can also use an Infrared Thermometer to measure each 200mm interval along the wire and plot the recorded data against the distance from the boiling water. The plot with the greatest difference from between 0mm and 1000mm will most likely be the worst thermal conductor. The produced plot should look similar to the one below.

Comparison

Below is a list of metals along with their thermal conductivity value. The higher the thermal conductivity value, the better thermal conductor that material will be.

Conclusion

Metals transfer heat via accumulated energy in the free electrons of the metal atoms, these electrons will collide with one another transferring their kinetic energy. This billiard like interaction will propagate throughout the metal until the energy is uniformly spread. Copper is usually considered the best thermal conductor on a thermal conductivity to price ratio. The only metal surpassing Copper is Silver with a thermal conductivity of 429.77 W/m-K. With this in mind, it would be to no surprise if the copper wire is found to have the have the highest temperature across all 200mm intervals and the highest degree of melted candles. Part Two of this experiment series will look at the variations in thermal conductivity due to length of a given material.

Heat energy is constantly being transferred from one substance to another. Heat energy always moves from the hotter material to the colder material. When you hold an ice cube, it might feel like the coldness is creeping up your hand, but it’s actually the other way around—the heat of your body transfers to the ice cube, which results in the ice cube obtaining a higher temperature and eventually melting.

Conduction is the most efficient form of heat transfer. In conduction, molecules of the warmer substance are moving faster than the molecules of the cooler substance. When the faster moving molecules collide with the slower moving molecules of the cooler substance, some of energy of the warmer substance is passed on. The cooler molecules that were directly collided with are moving faster, and when they collide with the surrounding cool molecules, they start moving faster too. Conduction is kind of like the game “telephone,” where the message is passed on by every individual in the circle.

The speed of conduction depends on how different the temperatures of the two objects are, how far apart they are, and what type of materials are conducting the heat. For instance, metal is a far better conductor than Styrofoam. That’s why metal is used for cooking and Styrofoam is used for the disposable coffee cups.

Materials

• Refrigerated butter or margarine
• Long metal spoon
• Pony beads
• Large glass Jar
• Hot tap water
• Timer

Procedure

1. Using tiny bits of cold butter, secure the three beads to the spoon handle. Make a hypothesis as to which bead will fall off the spoon first.
2. Have a grown-up fill the jar with enough hot water so that just the bowl of the spoon is submerged.
3. Place the spoon in the water, set the timer, and watch.

Results

You are likely to see bead A drop off first, then bead B, and then bead C. The time it takes to do this depends on how warm your water is, and the type of butter and spoon you used.

Remember that conduction involves direct collisions between the molecules. For your particular heat transfer experiment, the source of the heat energy is the warm water. The molecules of the warm water first collide with the metal molecules in the bowl of the spoon. The molecules in the bowl of the spoon are moving faster, and they are closest to the molecules in the lowest part of the handle, so that is the next place the heat energy is transferred. The first of part of handle to get the conducted heat energy is under bead A, so the butter under that bead softened, and the bead fell off. The heat energy continued travelling along the spoon, reaching the butter under bead B next and bead C.

Disclaimer and Safety Precautions

Education.com provides the Science Fair Project Ideas for informational purposes only. Education.com does not make any guarantee or representation regarding the Science Fair Project Ideas and is not responsible or liable for any loss or damage, directly or indirectly, caused by your use of such information. By accessing the Science Fair Project Ideas, you waive and renounce any claims against Education.com that arise thereof. In addition, your access to Education.com’s website and Science Fair Project Ideas is covered by Education.com’s Privacy Policy and site Terms of Use, which include limitations on Education.com’s liability.

Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state’s handbook of Science Safety.

How heat affects things is sometimes difficult to understand. This simple heat experiment shows how heat causes molecules to move faster.

Simple Heat Experiment

Supplies you’ll need:

• 3 clear jars
• water
• food coloring
• masking tape
• markers
• thermometer

How to conduct the experiment:

1. Label the jars with the temperatures you are going to use in the experiment. We used room temperature water , hot water , and cold water .
   
2. Turn on your sink faucet and measure the temperature. Adjust the faucet so the temperature is about 72°F. Fill the jar labeled Room Temperature. Alternatively, you can fill a jar will cool tap water and let it sit out for day. The water will eventually become the same temperature as the room.
3. Fill the jar labeled Cold Water 3/4 of the way with cold tap water. Add ice to the jar to cool the water even farther. Remove the ice from the jar before finishing your experiment.
4. An adult should help with the Hot Water jar. Turn on your faucet as hot as it will go. Fill the jar labeled Hot Water with hot water. An adult could also heat up some water on the stove. Just be careful not to make it too hot.
5. Add a drop of food coloring to each of the jars and observe what happens over time.

Questions to Ask:

• What happens to the drop of food coloring?
• Does the food coloring behave the same in each of the jars? Why or why not?
• What is different about the jars?
• What can you say about the relationship between heat and the movement of molecules?

The Science Behind It

Molecules move faster when they are warmer and slower when they are colder. The drop of food coloring spreads out fastest in the hot water because the molecules are moving the fastest of the three jars. The food coloring spreads out fairly quickly in room temperature water and slowest in the cold water. Eventually the food coloring spreads throughout all three jars.

More Simple Science Experiments

• Physics for Kids: Exploring Color and Temperature – Conduct an experiment to find out h ow color affects the temperature of an object. Even preschoolers can complete the steps of this experiment on their own.
• This celery science experiment is a great way to make transpiration come alive.
• Try this simple jumping experiment perfect for toddlers and preschoolers. How far can you jump?

–>

About Trisha Stanley

Trisha is an educator with a passion for science literacy and mom to Aiden and Lily. She’s the creator of Inspiration Laboratories, a blog dedicated to encouraging learning through creativity and play, and Read Science, a blog that showcases science activities inspired by children’s books.

How heat affects things is sometimes difficult to understand. This simple heat experiment shows how heat causes molecules to move faster.

Simple Heat Experiment

Supplies you’ll need:

• 3 clear jars
• water
• food coloring
• masking tape
• markers
• thermometer

How to conduct the experiment:

1. Label the jars with the temperatures you are going to use in the experiment. We used room temperature water , hot water , and cold water .
   
2. Turn on your sink faucet and measure the temperature. Adjust the faucet so the temperature is about 72°F. Fill the jar labeled Room Temperature. Alternatively, you can fill a jar will cool tap water and let it sit out for day. The water will eventually become the same temperature as the room.
3. Fill the jar labeled Cold Water 3/4 of the way with cold tap water. Add ice to the jar to cool the water even farther. Remove the ice from the jar before finishing your experiment.
4. An adult should help with the Hot Water jar. Turn on your faucet as hot as it will go. Fill the jar labeled Hot Water with hot water. An adult could also heat up some water on the stove. Just be careful not to make it too hot.
5. Add a drop of food coloring to each of the jars and observe what happens over time.

Questions to Ask:

• What happens to the drop of food coloring?
• Does the food coloring behave the same in each of the jars? Why or why not?
• What is different about the jars?
• What can you say about the relationship between heat and the movement of molecules?

The Science Behind It

Molecules move faster when they are warmer and slower when they are colder. The drop of food coloring spreads out fastest in the hot water because the molecules are moving the fastest of the three jars. The food coloring spreads out fairly quickly in room temperature water and slowest in the cold water. Eventually the food coloring spreads throughout all three jars.

More Simple Science Experiments

• Physics for Kids: Exploring Color and Temperature – Conduct an experiment to find out h ow color affects the temperature of an object. Even preschoolers can complete the steps of this experiment on their own.
• This celery science experiment is a great way to make transpiration come alive.
• Try this simple jumping experiment perfect for toddlers and preschoolers. How far can you jump?

–>

About Trisha Stanley

Trisha is an educator with a passion for science literacy and mom to Aiden and Lily. She’s the creator of Inspiration Laboratories, a blog dedicated to encouraging learning through creativity and play, and Read Science, a blog that showcases science activities inspired by children’s books.

Let’s learn about heat and do a couple simple radiation and conduction experiments to learn how heat is transferred from one object to another.

When we open the oven to get out a pan of freshly baked cookies, we can feel the heat coming out of the oven. We can tell the temperature of the oven is a lot higher than the temperature of the room. If we stand outside in the sunshine on a summer day, we can feel the heat of the sun. We know we can feel heat, but what is heat?

Heat is a type of energy that can be transferred from one object to another. A warmer object will transfer it’s heat energy to a colder object and raise that object’s temperature. Heat can be transferred to objects in several different ways. One way is by radiation, and another is by conduction.

Learn more and get instructions for simple ways to experiment with radiation and conduction at 123Homeschool4Me.com.

More Physics Experiments

Reader Interactions

Comments

Davonne Parks says

I am totally geeking out over your entire site! This is SO cool! I’ve been homeschooling my kiddos for 9 years now and can’t believe I haven’t found you before today. Thank you for all of these awesome articles and resource links!

Marci Goodwin says

I’m so glad you found The Homeschool Scientist! Hopefully, it will help you all have some fun with science.

Save this idea for later!

Use these simple heat experiments to show kids how convection heat works and why heat rises right in front of their eyes. Fascinating science experiments for kids!

I’ve wanted to try convection heat experiments with my kids for quite some time now. It looked so magical and other-wordly to see all those pearly colors swirling around with the heat. We learned some valuable lessons about exactly where the heat from our stove is coming from, too, which is probably why it cooks food so unevenly!

If you conduct this experiment with a large group, I recommend using a hot plate. First, because it is easier to haul around, and secondly, it produces a more even, low heat, which is better for seeing swirls.

Our mixture eventually got to hot and it didn’t look as cool when the dye moved from place to place.

Learn what is convection heat for kids!

Learn About What is Convection for Kids!

Try this easy convection heat experiment in the classroom or at home!

The Science: How Convection Heat Works

When you heat a fluid, its density is reduced and volume is expanded. At first, the soap and the water is evenly disributed in the pan, but when it heats up, the liquids at the bottom get warm first. This causes them to become less dense and rise to the top. The cool liquid is pushed to the bottom of the pan, where it in turn is heated and pushed to the top.

The pearly soap and food coloring make this easy to see.

What You’ll Need for the Convection Heat Experiment:

Disclaimer: This post includes affiliate links for your convenience at no cost to you.

• Aluminum pie plate (or a regular pie or cake pan)
• Liquid food coloring
• A pearly shampoo or conditioner (we used my husband’s Old Spice, it was the only pearly soap we had!)
• Stove or hot plate

First, mix your soap and water in a 2 to 1 ratio with twice as much water as soap. You will want to just cover the bottom of the pan (at least, ours worked better with a shallow amount of water). Try not to make extra bubbles.

You can leave the mixture its original color, or add dye to the entire pan. Bo was excited to add the food coloring, which is why we dyed our base soap.

Turn the heat on low and wait. You will see the liquid starting to rise by the changes in the color of the soapy water.

Once it starts to turn over, it’s ready to add more dye.

Drop a drop or two of food coloring in different areas of the pan. Watch as it is slowly rolled into the other colors.

Convection heat at work!

Save this idea for later!

About Brenda Priddy

Brenda grew up thinking she hated science.

But when her 4-year- old daughter was more interested in reading science facts than fairy tales, Brenda realized she had to learn more about science to keep up with her daughter.

Through simple at-home science experiments, Brenda developed a passion for science and now acts as an advocate for STEM education for kids at her website STEAMsational.com.

STEAM activities for kids promote the idea that science, technology, engineering, art, and math can all work together to help kids become critical thinkers, problem solvers, and innovators!

Join us on our journey to discover just how much fun science experiments can be.

Introduction

We have previously seen that the main methods for heat transfer are conduction, convection, and radiation. Though these topics were treated singly, it is not unusual for all three methods to be operational at the same time.

Thermos Bottle

A thermos bottle is an excellent example demonstrating how all three methods are inhibited. A thermos bottle has a double wall that creates a vacuum, and a shiny surface inside of it. We’ve seen that the shiny part on the inside is an example of radiation, where heat is reflected back from the walls and back to the liquid. Heat conduction is inhibited by the use of insulators such as glass and plastic. Heat does escape, through the body and the lid, but very slowly. The vacuum inhibits convective currents and also conduction.

Cooking Food

Grilling, broiling, and cooking over an open flame when you go camping are examples of cooking by radiation. However, when you grill and place your food on the grates, conduction also comes into play. When the air becomes hot, convection currents are created between the air and the food.

When you bake a cake or pot roast, all three methods are once again involved. There are convection currents as the air becomes hot from the oven. The pan the food is in becomes hot due to conduction. The walls of the oven become hot, and this is due to radiation.

We have previously seen that when you boil or steam food, the air and the water is heated by convection. Solid food, however, is heated by conduction, as the atoms inside of it begin colliding with each other.

Aside from cooking, there are simple heat transfer experiments you can do at home.

A Simple Heat Conduction Experiment

Obtain objects of different materials. Ideally, they would be of the same geometry, such as rods made from wood, glass, aluminum, and iron. However, materials such as plastic, wooden, and metal silverware will do. You will also need a heat source such as hot water, a stove burner, a hot plate, or a candle. To make the measurements, use a watch or some other time keeping device, and a simple thermometer. To record your results, use a spreadsheet or graph paper.

For a direct measurement, use masking or electrical tape to attach the thermometer to an object. Submerge it partially in hot water, and take time and temperature readings every few seconds. Graph the temperature versus time by placing the dependent variable, temperature, on the y axis and the independent variable, time, on the x axis. Do this for every object. Compare your results.

For indirect measurements, melt a substance such as candle wax or paraffin on the object. Slowly heat the object, and record the time it takes for the substance to melt. If you are careful, the substance can also be ice, butter, or something similar. In this case, the holder would have to be a spoon.

Remember to use caution whenever doing heat transfer experiments, as the objects and sources will be hot.

In the next part, we will look at simple experiments you can do in convection and radiation.

References

Conceptual Physics by Paul Hewitt

Essential University Physics by Paul Wolfson

Fundamentals of Physics by Halliday, Resnick, and Walker

Physics for Scientists and Engineers by Douglas Giancoli

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Use only pantry ingredients!

Reactions that get colder!

Make honeycomb

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Pizza box solar oven

Control the Sun’s rays

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Lemon juice Christmas cards

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Make A Simple Thermometer

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Microwave soap

Why does this happen?

Get adult help please!

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Dry ice + spoons

Adult help please

Ice-cream in a bag

Yummy ice-cream making!

All about freezing points

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Liquid nitrogen + balloon

Cool air down. what happens?

Charles Law in action

Temperature and The Density of Water

Learn about density

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Try a conductivity experiment using easy-to-access metals

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Conductivity Experiment using Metal

A known property of metal is conduction.

Metals are excellent conductors of heat and electricity—heat energy and electrons travel very quickly through them.

You can experiment with both heat and electricity conduction using items from around your house.

(Adult supervision recommended.)

Collect a metal spoon, wooden spoon, and other kitchen implements to compare heat conductivity.

Set them in a glass jar of hot, but not boiling, water. Which ones heat up fastest?

The ends of the metal utensils should have felt hot first, because they conduct heat better.

For a little more excitement, try this activity again using only metal utensils, with a dab of cold butter on top of each utensil.

Which one loses its butter first? Why might that be?

Look at each utensil’s handle thickness and length as well as its top surface area (e.g., a wire whisk has less surface to heat the butter than a ladle does) for clues.

Also, keep in mind that some metals conduct heat better than others do.

Test an Object for Electric Conductivity

What You Need:

• C- or D-size battery
• Aluminum Foil
• Flashlight or other 1.5- or 3-volt bulb

What You Do:

1. Make a long ribbon wire out of the foil by cutting a piece about 18′ x 2′. Fold the foil lengthwise in fourths so that you form a ribbon. Hold or tape one end of this wire to the flat end (negative terminal) of the battery and wrap the other end tightly around the ‘threaded’ (screw) sides of the light bulb.

2. Now you’re ready to test various objects around your house to see if they conduct electricity. Do this by pressing the positive terminal of the battery (the end with a bump) to one side of an object, and the metal end of the light bulb to the other side. If the bulb lights up, a series circuit was formed: electric current can pass unobstructed through the wires from the battery to the light bulb to the battery again.

What are some variables that could keep the light bulb from shining even if the object it was touching was metal? Even though an object may be metal and otherwise a great conductor of electricity, a plastic or paint coating on it could break the circuit connection.

Safety note: Remember never to insert wires or another object into electrical outlets! The electricity generated by the battery for this experiment is in a safe amount, however.

Copper-plating Fun

Try this experiment: first clean pennies, then watch them oxidize and use them to cover (or plate) an iron nail with copper! Although newer pennies contain only a small amount of copper (2.5%), they still have enough for this project.

What You Need:

• Ceramic or plastic bowl
• Vinegar
• Salt
• Pennies
• Paper towels
• Ungalvanized iron nail

1. Fill the bottom of the bowl with vinegar, stir in a teaspoon of salt, and then put 10-15 dull pennies in. Let them sit for five minutes, then take them out and set them on a paper towel to dry. (Don’t dump out the vinegar and salt yet, though!) The pennies will be much shinier than before; this is because vinegar is an acid that ‘eats’ away the oxide layer on the penny that is making it dull. However, if you don’t rinse or dry the clean pennies, after a while you should see a blue layer appear on them. This is a copper oxide compound caused by copper and oxygen reacting with each other; the vinegar (acetic acid) and salt promote the reaction of oxygen with the copper.

2. Now stick an ungalvanized iron nail in the vinegar solution. If you look closely, you will see tiny bubbles along the sides of the nail. Let it sit for 30 minutes and then check to see if there is a dark-brown layer of copper on it. How does that happen? The vinegar solution contains copper from the pennies that it cleaned. When the solution reacts with the nail, it makes a chemical exchange that leaves a copper coating on the nail. When you take the nail out of the solution, the copper will be somewhat sticky; you can set it on a paper towel to dry. Your nail might not be entirely coated, but it will have enough copper on it to see.

You might try this experiment again using only pennies made before 1982 (made with 95% copper).

Did the nail get a copper coating more quickly or in the same amount of time?

Energy is transferred between the Earth’s surface and the atmosphere in a variety of ways, including radiation, conduction, and convection.
Credit: NOAA NWS

Conduction is one of the three main ways that heat energy moves from place to place. The other two ways heat moves around are radiation and convection. Conduction is the process by which heat energy is transmitted through collisions between neighboring atoms or molecules. Conduction occurs more readily in solids and liquids, where the particles are closer to together, than in gases, where particles are further apart. The rate of energy transfer by conduction is higher when there is a large temperature difference between the substances that are in contact.

Think of a frying pan set over an open camp stove. The fire’s heat causes molecules in the pan to vibrate faster, making it hotter. These vibrating molecules collide with their neighboring molecules, making them also vibrate faster. As these molecules collide, thermal energy is transferred via conduction to the rest of the pan. If you’ve ever touched the metal handle of a hot pan without a potholder, you have first-hand experience with heat conduction!

Some solids, such as metals, are good heat conductors. Not surprisingly, many pots and pans have insulated handles. Air (a mixture of gases) and water are poor conductors of thermal energy. They are called insulators.

Conduction in the Atmosphere

Conduction, radiation and convection all play a role in moving heat between Earth’s surface and the atmosphere. Since air is a poor conductor, most energy transfer by conduction occurs right near Earth’s surface. Conduction directly affects air temperature only a few centimeters into the atmosphere.

During the day, sunlight heats the ground, which in turn heats the air directly above it via conduction. At night, the ground cools and the heat flows from the warmer air directly above to the cooler ground via conduction.

On clear, sunny days with little or no wind, air temperature can be much higher right near the ground that just a short way above. Although sunlight warms the surface, heat flow from the surface to the air above is limited by the poor conductivity of air. A series of thermometers mounted at different heights above the ground would reveal that air temperature falls off rapidly with height.