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

What is the mass of $2$ litres of nitrogen at $22.4$ atmospheric pressure and $273\ K$ 

  1. $28\ g$
  2. $14 \times 22.4 g$
  3. $56\ g$
  4. $none\ of\ these$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Consider STP conditions:
 
1) 1 mol = 22.4 L of gas; 1 mol of Nitrogen gas = 14 g
 
2) Therefore, 22.4 L Nitrogen gas = 14 g → 2 L Nitrogen = 1.25 g
 

3) This is at a standard pressure of 1 atm. So, 22.4 atm pressure corresponds to 22.4 × 1.25 = 28 g  

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

A sphere floats in water just submerged as shown in the diagram. If atmospheric pressure is neglected

  1. Force exerted by liquid on lower half of sphere is $\dfrac{4\rho\pi\ R^{2}}{3}g$

  2. Force exerted by liquid on lower half of sphere and upper half of sphere is same in magnitude
  3. Ratio of magnitude of forces exerted by liquid on lower and upper half of sphere is $5:1$
  4. Ratio of magnitude of forces exerted by liquid on lower and upper half of sphere is $4:1$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

For a sphere just submerged, the pressure varies with depth. The force on the lower half is greater than the force on the upper half due to the hydrostatic pressure gradient, resulting in a ratio of 5:1.

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

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

  1. $33.3 kPa$
  2. $66.7kPa$
  3. $3.33 MPa$
  4. $6.67 MPa$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Since the mercury rises only $50cm$ it implies the rest of the excess atmospheric pressure is being countered by the pressure at the top of the tube.
So pressure at top=atmospheric pressure - $50cm$ of Hg=$(75-50)cm=25cm$ of Hg=$1/3\times 100kPa= 33.33kPa$

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

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
  1. A-$1$, B-$4$, C-$2$, D-$3$
  2. A-$4$, B-$2$, C-$5$, D-$1$
  3. A-$2$, B-$3$, C-$5$, D-$4$
  4. A-$4$, B-$3$, C-$2$, D-$1$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Barometer measures atmospheric pressure (A-4). Chronometer measures time (B-3). Sextant measures angular distances (C-2). Quadrant measures altitudes/angles (D-1).

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

As the vertical height from mean sea level increases, the atmospheric pressure decreases.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

With increase in vertical height, the atmospheric pressure falls. Fall in pressure means that the temperature also falls. This is because pressure is directly proportional to Temperature and vice versa.