Physics · Geography

Atmospheric Physics and Humidity

878 Questions

Study the principles of atmospheric physics and humidity through these practice questions. Key subjects include the rate of evaporation, temperature inversions, and relative humidity measurements. These concepts are vital for geography and physics exams.

Evaporation and condensationRelative humidity conceptsAtmospheric pressure effectsTemperature inversion

Atmospheric Physics and Humidity Questions

Multiple choice physics pressure in liquids and gases common consequences of the atmospheric pressure atmospheric pressure and its consequences important points about atmospheric pressure

Water is not used as a barometric liquid because 

  1. it is difficult to have a barometer tube 11 m long.

  2. water vaporises under vacuum conditions.

  3. water sticks to the side of glass tube.

  4. all the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Mercury is more dense. Its relative density is $13.534$ times that of water. So, to measure the atmospheric pressure, which is $760 mm$ of mercury you need a barometer ,with mercury, of length slightly more than $0.76 m$, say one meter to cover the special cases of some higher  pressure. If you use water, you have to have the length of barometer of  length (or height)  $13.534$ times the length of mercury barometer, which  may be more than $11 m$ in length. 


Further mercury, being a metal has the shining quality which highlight its reading clear. Also mercury, having comparatively lower specific heat and good conductor of heat, could come to the same temperature of the atmosphere more quickly.

Multiple choice physics pressure in liquids and gases common consequences of the atmospheric pressure atmospheric pressure and its consequences important points about atmospheric pressure

Fill in blanks. 
Atmosphere pressure _________ with increase in altitude 

  1. increases

  2. decreases

  3. remains same

  4. cannot be determined
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Pressure with Height: pressure decreases with increasing altitude. The pressure at any level in the atmosphere may be interpreted as the total weight of the air above a unit area at any elevation. At higher elevations, there are fewer air molecules above a given surface than a similar surface at lower levels. For example, there are fewer molecules above the 50 km surface that are found above the 12 km surface, which is why the pressure is less at 50 km.

Hence, Atmosphere pressure decrease with an increase in altitude 

Multiple choice physics pressure in liquids and gases common consequences of the atmospheric pressure atmospheric pressure and its consequences important points about atmospheric pressure

By blowing between two balloons hanging close to each other you observe that they come closer. A similar phenomenon is seen in

  1. The lifting of an aeroplane

  2. Kite flying

  3. The lifting of balloon filled with

  4. Take off of rocket
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Due to present difference.

Multiple choice physics pressure in liquids and gases common consequences of the atmospheric pressure atmospheric pressure and its consequences important points about atmospheric pressure

The density of the atmosphere at sea level is 1.29 $kg/m^{2}$. assume that it does not change with altitude. then how high would the atmosphere extend?

  1. 3 km

  2. 7 km

  3. 8 km

  4. 9 km
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
We know that $p=pgh$
p is atmospheric pressure, g in acceration due to gravity
$p = 1.29 kg/m^{2} ; p-=1.013\times 10\, N/m$
$\therefore h=\dfrac{p}{pg}=\dfrac{1.013\times 10^{5}}{1.29\times 9.8}$  $= 8013 \,km$
hence atmospheric extended 8013 km high from the sea level
Multiple choice physics pressure in liquids and gases common consequences of the atmospheric pressure atmospheric pressure and its consequences important points about atmospheric pressure

we do not get crushed by the atmospheric pressure as the out internal pressure and the atmospheric pressure are?

  1. equal

  2. greater

  3. lower

  4. none of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

We don't get crushed by atmospheric pressure (about 1 kg per square cm) because our internal body pressure is equal to the atmospheric pressure. This balance of pressures prevents our bodies from collapsing. If there were a significant pressure difference, it would cause serious damage - like when divers get the bends from rapid pressure changes.

Multiple choice separation of components of mixtures methods of separation elements, compounds and mixtures chemistry

At higher altitudes the boiling point of liquid is lowered because :

  1. temperature is low

  2. pressure is high

  3. temperature is high

  4. atmospheric pressure is low
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A liquid reaches its boiling point when its vapor pressure is equal to the atmosphere around it.

 Because the presence of solute lower the vapor pressure, the boiling point is raised

Multiple choice various types of barometer fluids physics

Atmospheric pressure decreases by $1cm$ of mercury for every

  1. $125m$ increase in altitude
  2. $125m$ decrease in altitude
  3. $75m$ increase in altitude
  4. $75m$ decrease in altitude
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The atmospheric pressure decreases by $1cm$ for every $125m$ increase in height.

Multiple choice various types of barometer fluids physics

The vertical height of mercury in a simple barometer is ________  the area of cross-section of barometer tube.

  1. independent of

  2. dependent on

  3. can't say

  4. none
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

No, it doesn't depend on the cross-section of the tube.

Multiple choice various types of barometer fluids physics
When atmospheric pressure increases, the rod present at the upper end of the metallic box of the Aneroid barometer

  1. gets elevated

  2. gets depressed

  3. remains static

  4. None
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Aneroid barometers are popular for their light weight and size which increases its portability. The Aneroid barometer uses a small, flexible metal box called an aneroid cell (capsule). The evacuated capsule (or usually several capsules, stacked to add up their movements) is prevented from collapsing by a strong spring which is corrugated in form of a diaphragm. Small changes in external air pressure cause the cell to expand or contract. This expansion and contraction drives mechanical levers such that the tiny movements of the capsule are amplified and displayed on the face of the aneroid barometer.  When atmospheric pressure increases, the spring in upper end of box gets depressed and the reading is thus visible due to the elastic potential energy stored in the spring due to compression which pushes the diaphragm inside.

Multiple choice various types of barometer fluids physics
The flat spring present in Aneroid barometer

  1. Depresses the rod

  2. Elevates the rod

  3. Protects the diaphragm from collapsing

  4. Decreases the atmospheric pressure
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Aneroid barometers are popular for their light weight and size which increases its portability. The Aneroid barometer uses a small, flexible metal box called an aneroid cell (capsule). The evacuated capsule (or usually several capsules, stacked to add up their movements) is prevented from collapsing by a strong spring which is corrugated in form of a diaphragm. Small changes in external air pressure cause the cell to expand or contract. 

Multiple choice various types of barometer fluids physics
When atmospheric pressure decreases, the diaphragm of Aneroid barometer

  1. Bulges out

  2. Bulges in

  3. Get depressed

  4. None
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Aneroid barometers are popular for their light weight and size which increases its portability. The Aneroid barometer uses a small, flexible metal box called an aneroid cell (capsule). The evacuated capsule (or usually several capsules, stacked to add up their movements) is prevented from collapsing by a strong spring which is corrugated in form of a diaphragm. Small changes in external air pressure cause the cell to expand or contract. This expansion and contraction drives mechanical levers such that the tiny movements of the capsule are amplified and displayed on the face of the aneroid barometer.  When atmospheric pressure increases, the spring in upper end of box gets depressed and the reading is thus visible due to the elastic potential energy stored in the spring due to compression.

When the pressure decreases, the diaphragm to which spring is attached bulges out, showing the reading in the opposite direction.

Multiple choice various types of barometer fluids physics
What is the advantage of negligible vapour pressure of mercury.

  1. It does not affect the barometric height

  2. It gives the correct reading

  3. It is easily seen while taking the reading

  4. All the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The surface of mercury is shiny and opaque. Therefore it is easily seen while taking the observation. The vapor pressure of mercury is negligible. Hence the barometric height is not affected. The mercury neither sticks nor wets the glass tube.