thermal energy. temperature is a measure of… the total amount of energy in an object the total...
TRANSCRIPT
Thermal energy
Temperature is a measure of…
• The total amount of energy in an object
• The total amount of thermal energy in an object
• How much heat something gives off
• How fast the molecules in an object are moving
Heat is…
• Energy given off or absorbed by an object
• A measure of the motion of the molecules in an object
• The total amount of molecular energy in an object
How do we measure temperature?
Think about using a thermometer
How does the thermometer know how hot the substance is?
• The molecules of the substance bump into the thermometer and transfer energy. How often and how hard they bump into the thermometer are directly related to their speed.
• Temperature turns out to be related to the average speed of the molecules in a substance.
• Temperature is not a measure of the total amount of energy in an object.
• Thermal Energy = internal energy = a measure of the total kinetic and potential energy in an object
Name Water Freezes Room Temperature
Water Boils Absolute Zero
Fahrenheit32 70 212 -459
Celsiusq 21 100 -273
Kelvin 273 274 273 0
Temperature Converter
• http://www.onlineconversion.com/temperature.htm
• Since there is a minimum kinetic energy for particles(0 J), there is a lowest possible temperature-absolute zero.
Temperature and heat
• When you add heat energy to an object its temperature may or may not increase.
• Since heat is energy it can be measured in joules.
• 1 calorie is the amount of heat needed to raise the temperature of water by one degree.
• The amount of heat energy required to raise the temperature of a substance by 1o C is called specific heat capacity or specific heat.
Calculating Heat energy
• H=mcΔt• Where• H = heat energy added or removed• .m=mass• C = specific heat• Δt = change in temperature
Ways of using heat
• Forced air system-
Force heat
Two pipe system
Solar heating
• There is a passive solar heat-receive sunlight during day and are stored.
• Active solar heating-receives solar energy from panels on south side
Thermodynamics
• First law of thermodynamics-
• Second law of thermodynamics