Define Molecular
mass.
Molecular mass is defined as the ratio between total mass of
the mixture to the total number of moles available in the mixture.
What is isothermal
compressibility?
Isothermal compressibility is defined as the change in
volume with change in pressure per unit volume keeping the temperature
constant.
What is psychrometry?
The science which deals with the study of behavior of moist
air (mixture of dry air and water vapour) is known as psychrometry.
What is difference
between absolute humidity and relative humidity?
Absolute humidity is the mass of water vapour present in one
kg of dry air.
Relative humidity is the ratio of the actual mass of water
vapour present in one kg of dry air at the given temperature to the maximum mass of water vapour it can
with hold at the same temperature.
Absolute humidity is expressed in terms of kg/kg of dry air.
Relative humidity is expressed in terms of percentage.
What is effective temperature?
The effective temperature is a measure of feeling warmth or
cold to the human body in response to the air temperature, moisture content and
air motion. If the air at different DBT and RH condition carries the same
amount of heat as the heat carried by the air at temperature T and 100% RH,
then the temperature T is known as effective temperature.
What is Relative
humidity?
It is defined as the ratio of partial pressure of water
vapour (pw) in a mixture to the saturation pressure (ps) of pure water at the
same temperature of mixture.
What is the
difference between heat and internal energy?
Heat is the measure
of energy transferred between objects at different temperatures. Internal energy measures the energy that is
inside the object as kinetic energy of the object’s constituent particles and
potential energy between them. An object
that is perfectly insulated from the outside world would have some internal
energy (how much depends on its temperature), but would have no heat.
What is wet bulb
temperature (WBT)?
It is the temperature recorded by a thermometer whose bulb
is covered with cotton wick (wet)
saturated with water. The wet bulb temperature may be the
measure of enthalpy of air. WBT is the lowest temperature recorded by moistened
bulb.
What is dew point
depression?
It is the difference between dry bulb temperature and dew
point temperature of air vapour mixture.