Thermal Energy and Matter!!!!
~ WORK AND HEAT ~
~Heat is the transfer of thermal energy from one object to another as the result of a difference in temperature.
~Heat flows spontaneously from hot objects to cold objects.
~Friction produces heat.
~Heat flows spontaneously from hot objects to cold objects.
~Friction produces heat.
bacon;D
Cooking bacon is an example of using work and heat. The heat from your kitchen stove transfers to the pan. The pan then absorbs the heat and cooks the bacon. It takes work to move the spatula around and flip the bacon. At the end, your left with a hot, yummy piece of meat:).
~ TEMPERATURE ~
~Temperature is a measure of how hot or cold something is compared to a reference point.
~On the Celcius scale, the reference points for temperature are the freezing and boiling points of water.
~When an object heats up, on average, the paticles move faster. Also the temperature increases.
~Temperature is related to the average kinetic energy of the particles in an object due to their random motions through space.
~~ To measure heat with Fahrenheit or Celsius, you use a thermometer. The thermometer below shows Celsius on the right, the boiling point is 100 degrees C, and the freezing point is 0 degrees C.
~On the Celcius scale, the reference points for temperature are the freezing and boiling points of water.
~When an object heats up, on average, the paticles move faster. Also the temperature increases.
~Temperature is related to the average kinetic energy of the particles in an object due to their random motions through space.
~~ To measure heat with Fahrenheit or Celsius, you use a thermometer. The thermometer below shows Celsius on the right, the boiling point is 100 degrees C, and the freezing point is 0 degrees C.
~THERMAL ENERGY~
~Thermal energy is the total potential and kinetic energy of all the particles in an object.
~Thermal energy depends upon the mass, temperature, and phase (solid, liquid, or gas) of an object.
~Two substances can be at the same temperatures and have different thermal charges.
~If you have a cup of soda and a pitcher of kool-aid, both at the same temperature, the pitcher of kool-aid has more thermal energy. Thermal Energy depends on mass, and the pitcher of kool-aid has more mass. They both have the same kinetic energy, since they are at the same temperatures. But, since the pitcher has more particles and a larger mass, it has a larger thermal energy then the cup of soda.
~Thermal energy depends upon the mass, temperature, and phase (solid, liquid, or gas) of an object.
~Two substances can be at the same temperatures and have different thermal charges.
~If you have a cup of soda and a pitcher of kool-aid, both at the same temperature, the pitcher of kool-aid has more thermal energy. Thermal Energy depends on mass, and the pitcher of kool-aid has more mass. They both have the same kinetic energy, since they are at the same temperatures. But, since the pitcher has more particles and a larger mass, it has a larger thermal energy then the cup of soda.
~ THERMAL EXPANSION AND CONTRACTION ~
~Thermal expansion is the increase in volume of a material due to a temperature increase.
~Thermal contraction is the decrease in volume of a material due to a temperature decrease.
~Thermal expansion occurs because particles of matter tend to move farther apart as tempertaure increases.
~Thermal contraction occurs because particles of matter come closer together as the temperature decreases.
~Gases expand more than liquids, and liquids expand more than solids.
~Thermal contraction is the decrease in volume of a material due to a temperature decrease.
~Thermal expansion occurs because particles of matter tend to move farther apart as tempertaure increases.
~Thermal contraction occurs because particles of matter come closer together as the temperature decreases.
~Gases expand more than liquids, and liquids expand more than solids.
Thermal expansion
| Temperature increases
Temperature decreases | Particles move farther apart
Particles move closer together | Volume increases
Volumer decreases |
When you take a balloon outside it shrinks, but when you bring it back inside it expands. As temperature decreases, the particles that make up the air inside the balloon move more slowly, on average. Slower particles collide less often and exert less force, so gas pressure decreases and the balloon shrinks. When temperature rises, pressure increases and the balloon expands.
~ SPECIFIC HEAT ~
~Specific heat is the amount of heat needed to raise the temperature of one gram of material by one degree Celsius.
~The lower a material's specific heat, the more its temperature increases when heat is absorbed.
~ If equal masses of iron and plastic absorb the same heat, the iron's temperature rises more. Iron's specific heat is lower than plastic's specific heat; thus the metal's temperature is higher.
~One calorie is the energy needed to raise the temperature of one gram of water by one degree Celcius.\~1 Calorie= 4.184 Joules
~The heat (Q) took up by a material equals the product of the mass (m), the specific heat (c), and the change in temperature (T).
Q=m * c * T
~The lower a material's specific heat, the more its temperature increases when heat is absorbed.
~ If equal masses of iron and plastic absorb the same heat, the iron's temperature rises more. Iron's specific heat is lower than plastic's specific heat; thus the metal's temperature is higher.
~One calorie is the energy needed to raise the temperature of one gram of water by one degree Celcius.\~1 Calorie= 4.184 Joules
~The heat (Q) took up by a material equals the product of the mass (m), the specific heat (c), and the change in temperature (T).
Q=m * c * T
Material-Water
-Plastic -Air -Iron -Silver | Specific Heat-4.18
-1.84-2.09 -1.01 -0.449 -0.235 |
~ Measuring Heat Changes ~
~A calorimeter is used to measure changes in thermal energy.
~A calorimeter uses the principle that heat flows from a hotter object to a colder object until both reach the same temperature.
~According to the law of Conservation of energy, the thermal energy released by a test sample is equal to the thermal energy absorbed by its surroundings.
~A calorimeter uses the principle that heat flows from a hotter object to a colder object until both reach the same temperature.
~According to the law of Conservation of energy, the thermal energy released by a test sample is equal to the thermal energy absorbed by its surroundings.