3.2 Notes Heat

3.2 Notes What is heat? What is heat? -The transfer of energy between objects of different temperatures -Heat transfers from hot to cold until both temperatures of the different objects are the same. Once they are the same, there is no more heat. -Heat transfers from hot to cold until both temperatures of the different objects are the same. Once they are the same, there is no more heat. What is NOT heat? What is NOT heat? - Heat does not always mean HOT (misunderstanding)

What is transferred first? The warm from your body to the stethoscope The warm from your body to the stethoscopeOr The cold from the stethoscope to your body The cold from the stethoscope to your body

What is transferred first? Warm always transfers before cold because cold particles are denser than warm particles. Therefore, warm is faster. Warm always transfers before cold because cold particles are denser than warm particles. Therefore, warm is faster.

3.2 Notes There are 3 types of heat: There are 3 types of heat: 1. Conduction – the transfer of heat by touch 2. Convection – the transfer of heat through liquids & gases 3. Radiation – the transfer of heat through space (air – not touching)

3.2 Notes Conduction – the transfer of heat by touch Conduction – the transfer of heat by touch A solid touching a solid A solid touching a solid A liquid touching a solid A liquid touching a solid Anything touching a solid is conduction Anything touching a solid is conduction (i.e. – spoon touching a bowl, a soda can in ice water, lava touching the ground) (i.e. – spoon touching a bowl, a soda can in ice water, lava touching the ground)

3.2 Notes Convection – the transfer of heat through liquids Convection – the transfer of heat through liquids Must be two liquids of different temperatures in order for it to be convection (no solids allowed ;) Must be two liquids of different temperatures in order for it to be convection (no solids allowed ;) (i.e. – boiling water mixed with cold water, a warm soda mixed with cold orange juice) (i.e. – boiling water mixed with cold water, a warm soda mixed with cold orange juice)

3.2 Notes Radiation – the transfer of heat through space (air) Radiation – the transfer of heat through space (air) Air can change the temperature of a liquid or solid. Air can change the temperature of a liquid or solid. (i.e. – a heater heating a cool room, an air conditioner cooling a warm room, the sun heating a rock, the sun heating the ocean) (i.e. – a heater heating a cool room, an air conditioner cooling a warm room, the sun heating a rock, the sun heating the ocean)

Can you think of more examples? Write down in your notes 3 more examples that we have not already talked about for each type of heat. Write down in your notes 3 more examples that we have not already talked about for each type of heat. Conduction ConvectionRadiation Conduction ConvectionRadiation