Heat Energy 5th Grade
What is Thermal Energy Transfer? There are three ways heat can move through a system: Conduction: the transfer of thermal energy from one object directly into another ( ex: heat from the iron moves directly into the clothing). An object is touching a hotter object so, thermal energy will flow from hotter object directly to the cooler object.
Conduction The molecules do not have to be the same substance. http://www.theelusivefish.com/articles/wp-content/uploads/2007/09/hot-stove.jpg
The metal conducts heat from the cup Example 1 http://www.vernier.com/caliper/fall07/images/heat_transfer_large.jpg The metal conducts heat from the cup of warm water to the cup of cool water.
Your Coke becomes cold because the heat from the soda Example 2 http://www.photoanswers.co.uk/ImgGalleryTn/91/10191/2417_16333.jpg Your Coke becomes cold because the heat from the soda transfers into the ice, not the other way around.
What is Thermal Energy Transfer? There are three ways heat can move through a system: Convection: the transfer of thermal energy through the movement of a gas or a liquid. As a gas or liquid is heated, the heat causes it to move upward, carrying heat to the area above the heat source (heated air moves up, carrying thermal energy to the air above it)
Convection
The radiator warms the room by warming the http://www.eeb.ucla.edu/test/faculty/nezlin/Lecture1/Fig0803.jpg The radiator warms the room by warming the air around it. Then the warm air transfers heat to the rest of the room through convection.
Where is the freezer compartment put in a fridge? Cold air sinks Where is the freezer compartment put in a fridge? Freezer compartment It is warmer at the bottom, so this warmer air rises and a convection current is set up. It is put at the top, because cool air sinks, so it cools the food on the way down.
Why is it windy at the seaside?
The third method of heat transfer How does heat energy get from the Sun to the Earth? There are no particles between the Sun and the Earth so it CANNOT travel by conduction or by convection. RADIATION ?
What is Thermal Energy Transfer? Radiation: the transfer of energy by waves that move through matter and space. Solar Energy gives infrared waves. ( heat waves). Not all radiation from the sun reaches Earth’s surface. Some of it is reflected back into space by the atmosphere. Reflection occurs when heat or light bounces off an object. Radiation carries thermal energy from the lamp to the food.
The heat from the campfire transfers into your marshmallow, giving you a yummy, gooey treat! (Direct contact between the fire and your marshmallow will ruin it!) Example 2 http://www.lifefamilytraining.com/img/roasting-marshmallows.jpg
By the heat waves emitted from the fire Directly from handle to hand Through the movement of water By the heat waves emitted from the fire
What are Insulators and Conductors? Insulator: anything that slows the movement of thermal energy. Examples include: coolers, foam cups, fur coat. This slide includes a DE Science video clip about insulators and conductors. The lunch bag prevents heat in the air from moving Into the bag. This keeps the food in the bag cool.
What are Insulators and Conductors? Conductors- anything that allows thermal energy to move through it easily (most metals). . This slide includes a DE Science video clip about insulators and conductors. The cookie sheet is a conductor. The oven mitt is an insulator.
Why does metal feel colder than wood, if they are both at the same temperature? Metal is a conductor, wood is an insulator. Examples of metal conductors include: copper, Aluminium, silver & gold. Metal conducts the heat away from your hands. Wood does not conduct the heat away from your hands as well as the metal, so the wood feels warmer than the metal.
No matter what it feels like, cold does not transfer into your body. What is really happening here? Why do you wear heavy clothes when it’s cold outside? http://www.alaska-in-pictures.com/data/media/9/man-in-extreme-cold_355.jpg