Advertisements
Advertisements
Question
The weather report reads, "Temperature 20°C : Relative humidity 100%". What is the dew point?
Advertisements
Solution
Here,
Relative humidity = 100%
RH = `"Vapour pressure of air"/"SVP at the same temperature"` = 1
⇒ Vapour pressure of air = SVP at the same temperature
So , the air is saturated at `20^circ`C . So , dew point is `20^circ` C .
APPEARS IN
RELATED QUESTIONS
Can we define the temperature of (a) vacuum, (b) a single molecule?
A gas is kept in an enclosure. The pressure of the gas is reduced by pumping out some gas. Will the temperature of the gas decrease by Charles's low?
The mean square speed of the molecules of a gas at absolute temperature T is proportional to
The temperature and pressure at Simla are 15.0°C and 72.0 cm of mercury and at Kalka these are 35.0°C and 76.0 cm of mercury. Find the ratio of air density at Kalka to the air density at Simla.
Use R=8.314J K-1 mol-1
The mean speed of the molecules of a hydrogen sample equals the mean speed of the molecules of a helium sample. Calculate the ratio of the temperature of the hydrogen sample to the temperature of the helium sample.
Use R = 8.314 JK-1 mol-1
The condition of air in a closed room is described as follows. Temperature = 25°C, relative humidity = 60%, pressure = 104 kPa. If all the water vapour is removed from the room without changing the temperature, what will be the new pressure? The saturation vapour pressure at 25°C − 3.2 kPa.
Answer in brief:
What will happen to the mean square speed of the molecules of a gas if the temperature of the gas increases?
Answer in brief:
A gas in a cylinder is at pressure P. If the masses of all the molecules are made one-third of their original value and their speeds are doubled, then find the resultant pressure.
Answer in brief:
Show that rms velocity of an oxygen molecule is `sqrt2` times that of a sulfur dioxide molecule at S.T.P.
If the density of oxygen is 1.44 kg/m3 at a pressure of 105 N/m2, find the root mean square velocity of oxygen molecules.
Explain, on the basis of the kinetic theory of gases, how the pressure of a gas changes if its volume is reduced at a constant temperature.
Compare the rates of emission of heat by a blackbody maintained at 727°C and at 227°C, if the black bodies are surrounded by an enclosure (black) at 27°C. What would be the ratio of their rates of loss of heat?
Under which condition laws of Boyle, Charles, and Gay-Lussac are valid?
When photons of energy hv fall on a metal plate of work function 'W0', photoelectrons of maximum kinetic energy 'K' are ejected. If the frequency of the radiation is doubled, the maximum kinetic energy of the ejected photoelectrons will be ______.
The average K.E. of hydrogen molecules at 27° C is E. The average K.E. at 627° C is ____________.
Assuming the expression for the pressure exerted by the gas on the wall of the container, it can be shown that pressure is ______.
A molecule consists of two atoms each of mass 'm' and separated by a distance 'd'. At room temperature the average rotational kinetic energy is 'E', then its angular frequency is ______.
If a = 0. 72 and t = 0.04, then the value of r is ______.
Show that the average energy per molecule is directly proportional to the absolute temperature ‘T’ of the gas.
