Heat Transfer NOTES

Thermal Energy TOTAL energy of motion in molecules of a substance (therm=heat)

Temperature Average amount of energy in motion * Measured with a thermometer The longer the arrow the faster the movement

What is temperature? Average amount of thermal energy for each molecule of a substance Measured with a thermometer In degrees Celsius, Fahrenheit or Kelvin

How do thermometers work? The liquid in the bulb expands with heat and contracts with the lack of heat. Celsius is the scientific unit for measuring temperature because it is the most similar to the metric system.

Galileo Thermometer Galileo invented the first thermometer between 1500 and Uses glass spheres filled with colored alcohol. The spheres are designed to sink in sequence as the liquid inside is warmed and density increases.

Temperature points FreezingBoilingHuman Celsius0 C100 C37 C Fahrenheit32 F212 F98.7 F Kelvin273 K373 K310 K 0 K - absolute zerono motion in a substance

Temperature Conversions Celsius to Fahrenheit F = (C x 1.8) + 32 Fahrenheit to Celsius C = (F – 32) x.56 Can you explain how to convert Celsius to Kelvin?

Temperature Conversion Practice °F = __________ °C 2. 0 °F = __________ °C °F = __________ °C °F = __________ °C °F = __________ °C °C = __________ °F °C = __________ °F °C = __________ °F °C = __________ °F °C = __________ °F

Answers – Temperature Conversions °F = __23.9____ °C 2. 0 °F = __-17.8____ °C °F = _ 37_____ °C °F = __71.1____ °C °F = __-23.3___ °C °C = __113_____ °F °C = __86______ °F °C = ___14_____ °F °C = __392_____ °F °C = __-40_____ °F

HEAT Energy Transfers… from hotter object to COOLER object Heat hotcold Let’s try it: Rub your Hands together. Grab the legs of your chair. Can you feel the heat?

3 types of heat Transfer 1)Radiation: pure energy that moves through empty space infrared (not visible) felt as heat 2) Conduction: transfer of heat by touch Heat moves through a material without the material moving itself 3) Convection: transfer of heat by movement of fluid (liquid/gas) Heat moves through a material by actually moving the material itself

Radiation (infrared) Examples: *Feel warmth on face from sun= solar radiation * Warmth of a fire * Heat off car engine

More examples of radiation Heated driveways/ sidewalks * Heated floors

3 types of heat Transfer 1)Radiation: pure energy that moves through empty space infrared (not visible) felt as heat 2) Conduction: transfer of heat by touch Heat moves through a material without the material moving itself 3) Convection: transfer of heat by movement of fluid (liquid/gas) Heat moves through a material by actually moving the material itself

Conduction=touch Examples: * Hot sand on feet * Touching hot light bulb * Touching metal on hot seatbelt * Stove to pan handle * Melting ice in hand

3 types of heat Transfer 1)Radiation: pure energy that moves through empty space infrared (not visible) felt as heat 2) Conduction: transfer of heat by touch Heat moves through a material without the material moving itself 3) Convection: transfer of heat by movement of fluid (liquid/gas) Heat moves through a material by actually moving the material itself

Convection * Convection in water * Convection oven

Can you identify each type of heat transfer? 1.A metal spoon is placed in a hot drink and the handle becomes warm. 2.Water at the bottom of a pot takes in heat from the stove burner and moves upwards taking the heat with it. 3.If you stand in front of a campfire, you can feel the heat but if you move away from the campfire you feel cold.

* Holiday chimes * Spinning Lamps

LOOK AT ALL THREE:

Heat Transfer in the Troposphere radiation conduction * convection * CONVECTION is the most dominant heat transfer in the troposphere EARTH Atmosphere