Important points about atmospheric pressure - class-VIII
| Description: important points about atmospheric pressure | |
| Number of Questions: 64 | |
| Created by: Neema Pandya | |
| Tags: force pressure floating bodies force and pressure fluids pressure in liquids and gases physics pressure in fluids and atmospheric pressure |
A large bottle is fitted with a capillary siphon. Ratio of times taken to empty the bottle when it is filled with (i) water (ii) petroleum of relative density 0.8.
$( _{water} = 0.001poise, _{petroleum} = 0.002 poise, d _{water} = 1000 kg/m^3)$
Siphon will fail to work if
A ${ 16cm }^{ 3 }$ volume of water flows per second through a capillary tube of radius r cm and of length 1 cm, when connected to a pressure head of h cm of water. If a tube of the same length and radius r/2 is connected to the same pressure head, find the mass of water flowing per minute through the tube
If it takes $5$ minutes to fill a 15 litre bucket from a water tap of diameter $\frac{2}{\sqrt{\pi}}$ cm then the Reynolds number for the flow is (density of water = $10^3 kg/m^3$ and viscosity of water = $10^{-3}$Pa.s) close to
Atmospheric pressure at sea level is
Unit for pressure used in weather maps is millibar. 1 millibar is equal to
We sit in the room with windows open. Then
Atmospheric pressure is ______ $Nm^{-2}$ at sea level.
_________ invented a pump to extract air out of the vessel.
What happens when pressure inside a sealed can is less than the atmospheric pressure?
What happens, when the pressure inside a sealed bottle exceeds the atmospheric pressure?
In crushing can experiment the can gets crushed because of:
Which of the following is a unit of atmospheric pressure.
When a plane moves along the runway, the air above the wing speeds up more, So the pressure
An instrument commonly used for measurement of atmospheric pressure is known as
Which of the following are the examples of atmospheric pressure?
1 mm Hg is equal to
wherever the air pressure is higher, there will be a stronger force or push against an object. Is the statement True or False
The ordinary pressure of air surrounding us is
Specify heat of mercury is
A boy blows a balloon of volume $1$ litre to pressure of $10$ atmospheres in $10$ sec, the power is
Ice of water at $ 100^o $ is given 540 cal of beat and the steam formed occupation 1671 cc at the atmosphere pressure. Then workdone against atmosphere pressure in this procces is nearly
In the above problem what is the pressure necessary to accomplish this task $(g=9.8\ m/s^{2})$
What is the mass of $2$ litres of nitrogen at $22.4$ atmospheric pressure and $273\ K$
A sphere floats in water just submerged as shown in the diagram. If atmospheric pressure is neglected
A barometer tube, containing mercury, is lowered in a vessel containing mercury until only $50 cm$ of the tube is above the level of mercury in the vessel. If the atmospheric pressure is $75 cm$ of mercury, what is the pressure at the top of the tube
$2\ kg$ of water is converted into steam by boiling at atmospheric pressure. The volume changes from $2\times 10^{-3}\ m^{3}$ to $3.34\ m^{3}$. The work done by the system is about
On the surface of earth, the atmospheric pressure is minimum at the sea-level.
Match List I with List II and select the correct answer by using the codes given the lists.
| List I | List II |
|---|---|
| A. Baremeter | $1$. Used for Measuring altitudes and angles in navigation and astronomy |
| B. Chronometer | $2$. Used for measurement of angular distances between two digits |
| C. Sextant | $3$. Keeps the accurate time as the one that is used to determine longitude at sea |
| D. Quadrant | $4$. Used for measuring atmospheric pressure |
| $5$. An instrument used in the diagnosis of pregnancy |
As the vertical height from mean sea level increases, the atmospheric pressure decreases.
How does atmospheric pressure change with the change in altitude
The atmospheric pressure at sea level is :
A hydrogen-filled balloon expands as it rises and may even burst after rising very high in the atmosphere. This happens because
Why nose bleed when we go at high attitudes:
Atmospheric pressure .................... with altitude
Consider the following statements and identify the right ones.
I)Air pressure decreases when air descends.
ii) Air pressure at sea level is lower than at the mountain top.
What will happen to submaximal heart rate during exercise at altitude for any given level of submaximal oxygen consumption when compared to sea level?
It has been shown that those who successfully deal with altitude have
Which of the following strategies would likely result in the optimal adaptations?
Which of the following is a physiological change that has been shown to occur as a result of exposure to extreme altitudes?
Which of the following factors would help maintain body temperature in cold water?
Which of the following statements is false?
Which of the following pollutants does not affect lung function in normal adults but causes bronchoconstriction in asthmatics?
A narrow uniform glass tube $80\ cm$ long and open at both ends is half immersed in mercury. Then, the top of the tube is closed and it is taken out of mercury. A column of mercury $22\ cm$ long then remains in the tube. What is the atmospheric pressure?
If the mean free path of a gas is $\lambda$ at one atmospheric pressure, then its value at 5 atmospheric pressure will be (temperature is assumed to be constant)
one -meter long tube closed at both the ends is lying horizontally. A mercury column of length 0.1 m is filled in its middle and in rest in two parts air is filled at atmospheric pressure. when the tube is turned to verticle position then displacement of mercury column will be
In troposphere, temperature varies linearly with elevation as $T=T _0-ay$, where $T _0$ is the temperature at the earth surface, then:
A $2-m3$ weather balloon is loosely filled with helium at $1\ atm (76\ cm\ Hg)$ and at $27^{\circ}C$. At an elevation of $20,000\ ft$, the atmospheric pressure is down to $38\ cm\ Hg$ and the helium has expanded, being under no constraint from the confining bag. If the temperature at this elevation is $-48^{\circ}C$, the gas volume (in $m3)$ is
The atmospheric pressure on a hill can be ___ $cm$ of mercury.
How does pressure vary as we come from mountain top to sea level?
76 cm of mercury column exerts a pressure equal to that exerted by:
______ m of air column ,on an average ,will exert as much pressure as 1 cm column of mercury.
It takes much longer to cook food in the hills than in the plains, because
Water boils at a lower temperature than $100^o$C on a hill station, because.
Why does water boil below $100^o$C at higher altitudes?
If the the height $(h)$ at which the atmospheric pressure is reduced to half. Find the value $\displaystyle h$.
A fully loaded Boeing aircraft has a mass of $33\times 10^{5}$ kg. Its total wing area is $500 m^2$. It is in level flight with a speed of $960 km/h$. (a) Estimate the pressure difference between the lower and upper surfaces of the wings. (b) Estimate the fractional increase in the speed of the air on the upper surface of the wing relative to the lower surface. The density of air is $\rho = 1.2 kg m^{-3}$ and $g = 9.81 m^{-2}$.
Average density of air is:
If the air pressure is below 76cm,we can say that air pressure has:
Which of the following causes change in air pressure?