ENERGY CONSERVATION & TRANSFER 5.P.3.1 Explain how the properties of some materials change as a result of heating and cooling. CLEAR LEARNING GOAL AS A STUDENT I WILL BE ABLE TO IDENTIFY AND EXPLAIN THE DIRECTION THAT HEAT TRAVELS AMONG DIFFERENT OBJETS. Heat transfers throughout our environment all the time. Wherever you are, you are aware of things that are warm or cool. You also notice when things are getting hotter or colder. If you dive into a swimming pool or walk barefoot on a sidewalk in the summer you are feeling the effects of heat transfer. Transfer- Transfer is the movement from one place to another! Heat Energy • Energy is what makes things happen. • All materials are made of tiny particles called molecules. • Molecules are always moving. These Molecules are in motion. • The movement creates heat. • The amount of heat depends on how fast the molecules move. • As the molecules move faster, they take up more space and make the object expand. IMPORTANT!!! Heat transfer ALWAYS follows the following rule The direction of transfer always occurs from the hotter object to the cooler object. Think and Discuss with your group Does the ice in ice water cool the water or does the water melt the ice? Think- which is warmer water or ice? Tip- transfer of heat always goes from warmer substance to colder substance Think and Discuss with your group Your cold hand touches a warm hot chocolate mug. Does the mug warm your hand or does your cold hand cool the mug Think- which is warmer water or ice? Tip- transfer of heat always goes from warmer substance to colder substance Think and Discuss With your group come up with 3 examples of how heat transfers from hot to cool and write them EXTRA- come up with a story where heat is transferred from hot to cold. LAB #1 HEAT MOVEMENT Journal Response Question Thinking about your findings from the heat lab; in your Science journal, explain how heat moves from one object to another using three or more sentences. CLEAR LEARNING GOAL AS A STUDENT I WILL BE ABLE TO IDENTIFY AND EXPLAIN THE DIFFERENCES BETWEEN RADIATION, CONVECTION, AND CONDUCTION. HEAT TRANSFER In our environment, heat transfers to another object in three different ways. They are: 1. Radiation 2. Conduction 3. Convection * Remember all three ways follow the direction rule from hotter to colder. Graphic Organizer CONDUCTION Conduction is the transfer of thermal energy (heat) between things that are touching. EXAMPLE: Placing a spoon in a bowl of hot soup results is a hot spoon. OTHER EXAMPLES? CONVECTION Convection is the transfer of thermal energy (heat) through the up and down movement of liquids or gasses. Hot liquids/gasses rise and cooler liquids/gasses sink •This constant movement of up and down allows the liquid or gas to heat. EXAMPLE: Boiling Water, Air Masses, Hot Air Balloons RADIATION RADIATION is the transfer of thermal energy (heat) through open space. Objects/liquids/gasses do not need to be touching to transfer the heat. EXAMPLE: Sun warming the Earth, Warming Hands over Fire, Heat lamps at fast food restaurant. JOURNAL RESPONSE In your Science Journal, Draw a sketch of the following diagram, identify each method of heat transfer, label the diagram, and write three to four sentences explaining your reasoning. CLEAR LEARNING GOAL AS A STUDENT I WILL BE ABLE TO IDENTIFY AND EXPLAIN HEAT TRANSFER THROUGH CONDUCTION. CONDUCTION Conduction is the transfer of thermal energy (heat) between things that are touching. EXAMPLE: Placing a spoon in a bowl of hot soup results in a hot spoon. OTHER EXAMPLES? Some objects/materials allow heat to transfer through them more quickly than others. We consider these good conductors. CONDUCTION Two objects must touch or have direct contact!!! ONLY HAPPENS IN THE EVENT OF HEAT TRAVELING THROUGH SOLIDS CONDUCTION When you touch one hot surface to another, the hot molecules bump into the other molecules which makes them start to move faster. An object gets hotter from the movement of the molecules. Conduction When you heat a metal strip at one end, the heat travels to the other end. As you heat the metal, the molecules vibrate, these vibrations make the adjacent molecules vibrate, and so on and so on, the vibrations are passed along the metal and so is the heat. We call this? Conduction Conduction All solid objects conduct heat, some are better conductor than others. Metals are good conductors. CONDUCTION LAB Lab: Conduction Purpose: Experiment using conduction Materials 1) Metal Spoon 2) Paper Cup 3) Birthday Candle 4) Infrared Thermometer PROCEDURE 1. 2 3. 4. 5. 6. 7. OBJECT: Place your paper cup on a hard surface upside down Poke the birthday candle through the bottom of the cup and allow to stand straight Have your teacher light the candle at this time Place your spoon in the flame Observe what happens Place spoon in cold water Complete chart below STARTING TEMPERATURE: FINISHING TEMPERATURE: WHAT HAPPENED IN THE LAB? SPOON What did you observe during the lab? _____________________________________________________________ _____________________________________________________________ _____________________________________________________________ _____________________________________________________________ How do you know that lab demonstrated conduction? _____________________________________________________________ _____________________________________________________________ _____________________________________________________________ _____________________________________________________________ CONDUCTION VIDEO http://www.youtube.com/watch?v=wV7gzcKegdU Journal Response Question Thinking about your own house, when do you use conduction? Draw a diagram that shows when you use conduction, label the parts, and explain how and why your diagram is an example of conduction. CONVECTION Convection is the transfer of thermal energy (heat) through the up and down movement of liquids or gasses. Hot liquids/gasses rise and cooler liquids/gasses sink •This constant movement of up and down allows the liquid or gas to heat. EXAMPLE: Boiling Water, Air Masses, Hot Air Balloons CONVECTION CONVECTION OCCURS IN THE HEATING OF LIQUIDS OR GASSES ONLY DOES NOT OCCUR IN THE TRANSFER OF HEAT WITHIN SOLIDS CONVECTION As molecules heat up, the heat makes the molecules move more rapidly and expand. Which creates currents in liquids or gases – hot air rises and cold air sinks. EXAMPLES Cold air sinks Where is the freezer compartment put in a fridge? It is put at the top, because cool air sinks, so it cools the food on the way down. Freezer compartment It is warmer at the bottom, so this warmer air rises and a convection current is set up. CONVECTION VIDEO http://www.youtube.com/watch?v=IfeRaOb_E-s Journal Response Question IN THREE OR MORE SENTENCES EXPLAIN THE PROCESS OF CONVECTION AND DRAW A PICTURE THAT SHOWS AN EXAMPLE OF CONVECTION. CLEAR LEARNING GOAL AS A STUDENT I WILL BE ABLE TO IDENTIFY AND EXPLAIN THE HEAT TRANSFER PROCESS KNOWN AS RADIATION. Simple Radiation Demonstration To see the effects of radiation, students will need to coat the tip of a toothpick with a bit of wax as it melts and runs down the side of the candle. If they let the wax harden for a few moments, they can then move the toothpick slowly toward the flame. They must, however, approach the flame from below, and they should not let the wax tip touch the flame. Rather, when the tip gets a centimeter or two from the flame, they should see the wax begin to melt. Since the tip is not touching the flame, the wax cannot be melting due to conduction. Since the tip is below the flame, it cannot be melting due to convection. Instead, the wax melts because of the heat radiated from the flame. RADIATION RADIATION is the transfer of thermal energy (heat) through open space. Objects/liquids/gasses do not need to be touching to transfer the heat. EXAMPLE: Sun warming the Earth, Warming Hands over Fire, Heat lamps at fast food restaurant. RADIATION Release of invisible heat energy waves from the sun or fire. No movement of molecules to transfer heat. RADIATION When the radiant energy from the sun hits the earth, the earth soaks up the energy and changes it into heat Heat Transfer Video http://www.youtube.com/watch?v=7Y3mfAGVn1c&feat ure=related Journal Response Draw a picture of radiation and explain the process in three or more sentences. BE DESCRIPTIVE. Additional Heat Transfer Information http://www.teachersdomain.org/asset/lsps07_int_heatt ransfer/ CLEAR LEARNING GOAL AS A STUDENT I WILL BE ABLE TO IDENTIFY AND EXPLAIN THE DIFFERENCES BETWEEN MATERIALS THE ARE CONDUCTORS AND INSULATORS. CONDUCTORS & INSULATORS Some objects/materials allow heat to transfer through them more quickly than others. We consider these good conductors. Conductor- heat flows through conductors. (The heat flows along all the molecules!) Insulator An insulator is a material that partially or completely blocks the flow of heat. (They trap heat in one spot!) Conductor! A material in which molecules are able to move easily is a conductor. The best electrical conductors are metals. Example: Metal pot handle CONDUCTORS Objects that allow heat to flow through them. Conductors are usually made of metal. Copper, aluminum, silver, and gold are good conductors. A conductor is the opposite of an insulator. INSULATOR An insulator is a material, usually nonmetallic, that partially or completely blocks the flow of heat. Plastic, rubber, leather, glass, and ceramic are good insulating materials. An insulator is the opposite of a conductor CONDUCTORS AND INSULATORS LAB Lab: Conductors and Insulators Purpose: Differentiate between conductors and insulators Materials 1) Pie Pan 2) Sand 3) Tea lights 4) Large Container 5) Cold water 6) 6 Objects PROCEDURE 1. 2 3. 4. 5. 6. 7. 8. OBJECT: Copper Pipe PVC Pipe Aluminum Foil Wood Bolt Metal Strip Have your teacher light the tea lights Each member of your group should start with one object Complete properties section for each item Hold item on one end while heating the other end by holding it ABOVE the flame for 30 SECONDS ONLY! Observe whether heat travels through the object If item gets hot drop in cold water IMMEDIATELY REPEAT FOR EACH ITEM Complete Chart below PROPERTIES Color: Shiny or Dull: Metallic? Color: Shiny or Dull: Metallic? Color: Shiny or Dull: Metallic? Color: Shiny or Dull: Metallic? Color: Shiny or Dull: Metallic? Color: Shiny or Dull: Metallic? OBSERVATION: Conductor or (DID HEAT TRAVEL?) Insulator? Journal Response Question IN THREE OR MORE SENTENCES EXPLAIN HOW YOU CAN TELL IF AN OJBECT IS A CONDUCTOR OR INSULATOR. ADDITIONALLY, WRITE 3 EXAMPLES OF CONDUCTORS AND 3 EXAMPLES OF INSULATORS THAT WERE NOT USED IN THE LAB CLEAR LEARNING GOAL AS A STUDENT I WILL BE ABLE TO IDENTIFY MATERIALS THAT COULD BE USED AS INSULATORS AND CONDUCTORS HEAT TRANSFER In our environment, heat transfers to another object in three different ways. They are? * Remember all three ways follow the direction rule from hotter to colder. CONDUCTORS & INSULATORS Some objects/materials allow heat to transfer through them more quickly than others. We consider these good conductors. Conductor- heat flows through conductors. (The heat flows along all the molecules!) Insulator An insulator is a material that partially or completely blocks the flow of heat. (They trap heat in one spot!) CONDUCTORS Certain materials are conductors. These items will trap heat and allow things to stay WARM! Copper Aluminum Platinum Gold Silver Water People and Animals Trees INSULATORS CERTAIN MATERIALS ARE CONSIDRED INSULATORS. THESE ITEMS ARE GOOD FOR KEEPING THINGS COOL! Glass Porcelain Plastic Rubber Wood Foam CONDUCTORS & INSULATORS COLORS! Certain colors are also better for transferring heat. Some colors or finishes will reflect (or throw back) light or heat. While others will absorb (trap) heat. COLORS DARK COLORS ABSORB HEAT WHILE LIGHT COLORS REFLECT HEAT REFLECTIVE (SHINY) COLORS THROW HEAT BACK DULL COLORS TRAP HEAT PRACTICE PUT IN ORDER THE FOLLOWING COLORS THAT WOULD BE THE HOTTEST TO TOUCH AFTER SITTING IN THE SUN. Dull yellow Shiny White Shiny Black Dull Blue Emission experiment Four containers were filled with warm water. Which container would have the warmest water after ten minutes? Dull metal Shiny metal Shiny black Dull black shiny metal The __________ container would be the warmest after ten minutes because its shiny surface reflects heat radiation _______ back dull black into the container so less is lost. The ________ container emitting would be the coolest because it is the best at _______ heat radiation. Absorption experiment Four containers were placed in front of a heater. Which container would have the warmest water after ten minutes? Dull metal Shiny metal Shiny black Dull black dull black The __________ container would be the warmest after ten radiation minutes because its surface absorbs heat _______ the best. shiny metal The _________ container would be the coolest because it is absorbing the poorest at __________ heat radiation. VIDEO Discovery Education: Magic School Bus: In the Artic Journal Response Question IN THREE OR MORE SENTENCES EXPLAIN HOW A COLOR AND WHETHER IT IS SHINY OR NOT CAN BE USED TO KEEP AN OBJECT HOT OR COOL. ADDITIONALLY, WHAT COLOR AND MATERIAL WOULD YOU USE IF YOU WANTED TO KEEP WATER COOL?