UNIT ONE Flashcards
(24 cards)
Describe Heat
heat is thermal energy flowing from a higher temperature object to a lower temperature
What are the units that measure energy?
Calories, Kilocalories, Joules
Examples of Convention
Hot air naturally flowing upward above a heater
Specific heat of a material is the amount of energy required to do what?
to change 1 g of the material by 1°C or 1 K.
One calorie is the amount of energy required to what?
raise the temperature of 1 g of water by 1°C
Which two temperature scales are a US scientist most likely to use in his or her work?
Celsius and Kelvin
The warmth felt next to a hot fire is mainly due to what?
thermal radiation emitted by the fire
When energy is added to a substance at constant volume and pressure, its temperature increases except what
when the substance is undergoing a phase change
0.239 cal is equivalent to what?
1J
In the context of heat, radiation is the transfer of WHAT by WHAT?
thermal energy; electromagnetic radiation
The emission and absorption of electromagnetic radiation results in the transfer of thermal energy. The best example of this is what?
a microwave oven
Which of the following cannot be the only movement of thermal energy in an isolated system?
thermal energy transferred from a colder object to a hotter object
Convection is the transfer of WHAT along with moving matter.
thermal energy
Calorimetry is what?
the study of thermal energy exchange during thermodynamic processes
Thermal energy is being steadily added to a system. Which two effects do not occur at the same time?
phase change and temperature increase
Thermal energy is being steadily added to a system. Which two effects do not occur at the same time?
phase change and temperature increase
If one end of an iron bar is heated, what causes thermal energy to transfer to the other end?
conduction
The energy required to raise the temperature of 1 kg of water by 1°C is what?
1 kcal
The SI unit of measure for thermal energy is a what?
joule
Which of the following can cause objects to require different amounts of thermal energy to reach the same temperature?
therm, joule, BTU and degree Celsius
During a phase change, as energy is added, the temperature of a substance what?
Is constant
Which physical principle is the main foundation for solving thermal energy transfer problems for a particular system?
the law of conservation of energy (the first law of thermodynamics)
When does the flow of thermal energy stop?
when the objects are in thermal equilibrium
The “kcal” unit is
1000 calories
