Physics 1137 Self Test
What is an "ideal" gas
An ideal gas is a gas that precisely follows the ideal gas equation
What is Brownian motion?
Brownian motion is the random motion of a particle in a fluid
The ... is the metric unit for temperature
Celsius degree
Define conduction
Conduction is the transfer of heat by direct contact
Define convection
Convection is the transfer of heat by currents
What is diffusion?
Diffusion is the gradual mixing of molecules of two or more gases
Write the first law of thermodynamics
Energy can neither be created nor destroyed
What is entropy?
Entropy is the measure of how evenly heat is distributed in the universe
State the three main assumptions of the kinetic theory of gases
Gas molecules are widely separated Gas molecules move rapidly and freely in all directions Gas molecules frequently collide with one another and with the walls of their container
What law of physics did Mr. Fahrenheit discover while using his thermometer?
He discovered that each liquid has its own fixed freezing and boiling temperatures
Write the second law of thermodynamics
Heat always travels of its own accord from a region of high temperature to a region of low temperature
What is heat capacity?
Heat capacity is the amount of heat needed to raise a substance's temperature one degree Celsius
What is heat?
Heat is the total kinetic energy of all the molecules of an object
How does a bimetallic strip help to heat and cool a home?
It bends with temperature changes, and thus opens and closes a circuit in a thermostat
Why is the second law of thermodynamics a powerful argument for Creation?
It says that all spontaneous change tends toward disorder, showing that life had to begin with a high degree of order
The ... temperature scale is based on the absolute zero temperature
Kelvin
What is latent heat of fusion?
Latent heat of fusion is the amount of heat needed to convert one gram of a solid at its normal melting temperature into a liquid at the same temperature
What is latent heat of vaporization?
Latent heat of vaporization is the amount of heat needed to change one gram of a substance at its normal boiling temperature into a gas at the same temperature
Define radiation
Radiation is the transfer of energy by electromagnetic waves
How can some evaporation occur when a liquid has a temperature below its boiling point?
Some molecules of the liquid travel faster than average and possess enough kinetic energy to escape from the surface
What is specific heat?
Specific heat is the measure of the heat capacity of a substance
What is temperature?
Temperature is the average kinetic energy of the molecules of a substance
Contrast temperature and heat
Temperature is the average kinetic energy of the molecules of a substance; heat is the total kinetic energy of the molecules of a substance
State the law of heat exchange
The amount of heat given off by a hot substance equals the heat received by a cold substance
Give another name for the law of conservation of energy
The law of conservation of energy is also known as the first law of thermodynamics
What is thermodynamics?
Thermodynamics is the study of the movement of heat
List three ways to improve efficiency of heat engines
remove friction remove heat losses increase the temperature different between the heat source and the heat sink
List three factors that determine the total heat content of a body
specific heat temperature mass
The coefficient of linear expansion is ...
the fractional change in length of a solid for each degree Celsius change in temperature
We use a ... to measure temperature
thermometer
Under what two conditions may a gas behave differently than the "ideal" gas law predicts?
when the pressure is above a certain level when the temperature falls below a certain point
Write the third law of thermodynamics
A body cannot have zero entropy
What is a calorie?
A calorie is a metric unit of heat that will raise the temperature of one gram of water one degree Celsius
The ... is the unit of heat in the metric system
calorie
List three causes of ocean currents
convection prevailing winds spin of Earth
... solids readily transfer hear while ... solids transfer heat poorly
crystalline, amorphous
Refrigerators and air conditioners use ... and ... to produce cooler temperatures
evaporation, condesation
State the formula of the ideal gas law
k= PxV/T
Engineers must allow for ... in the construction of large bridges
linear expansion