Thermodynamics Chapter 1 True/False

temperature is an extensive property

false; temperature does not depend on the size of the system and therefore is intensive

according to Archimedes' principle, the magnitude of the buoyant force acting on a submerged body is equal to the weight of the body

false; the buoyant force has a magnitude equal to the weight of the displaced liquid

systems can be studied only from a macroscopic point of view

false; thermodynamics focuses a system microscopically

a closed system always contains the same matter; there is no transfer of matter across its boundary

true

body organs, such as the human heart, whose shapes change as they perform their normal functions can be studied as control volumes

true

both the Kelvin scale and the Rankine scale are absolute temperature scales

true

devices that measure pressure include barometers, Bourdon tube gages, and manometers

true

gage pressure indicates the difference between the absolute pressure of a system and the absolute pressure of the atmosphere existing outside the measuring device

true

if a system is isolated from its surroundings and no changes occur in its observable properties, the system was in equilibrium at the moment it was isolated

true

if the value of any property of a system changes with time, that system cannot be at steady state

true

in local surroundings at standard atmospheric pressure, a gage will indicate a pressure of 0.2 atm for a refrigerant whose absolute pressure is 1.2 atm

true

intensive properties may be functions of both position and time, whereas extensive properties can vary only with time

true

pressure is an intensive property

true

specific volume, the volume per unit of mass, is an intensive property whereas volume and mass are extensive properties

true

temperature is the property that is the same for each of two systems when they are in thermal equilibrium

true

the Rankine degree is a smaller temperature unit than the Kelvin degree

true

the kilogram for mass and the meter for length are examples of SI base units defined relative to fabricated objects

true

the pressure unit psia indicates an absolute pressure expressed in pounds force per square inch

true

the specific volume is the reciprocal of the density

true

the value of a temperature expressed using the Rankine scale is always higher than its value expressed using the Fahrenheit temperature scale

true

the volume of a closed system can change

true

volume is an extensive property

true

when a closed system undergoes a process between two specified states, the change in temperature between the end states is independent of details of the process

true

the value of the temperature expressed using the Celsius temperature scale is always higher than its value expressed using the Kelvin scale

false; a value expressed using the Kelvin scale is always 273.15 degrees higher than its value expressed using the Celsius scale

the composition of a closed system cannot change

false; combustion is an example of when the composition of the system changes as the initial combustible mixture becomes products of combustion

a control volume is a special type of closed system that does not interact in any way with its surroundings

false; control volume, also known as open system, involves mass flow across the boundary of the system

kilogram, second, foot, and newton are all examples of SI units

false; foot, a measure of length, is an example of an English unit; meter is an example of a unit of length which is SI

the pound force, lbf, is equal to the pound mass, lb

false; lbf is a unit of force and lb is a unit of mass

mass is an intensive property

false; mass depends on the size of the system and therefore is extensive