baro mano worksheet

7/23/2019 Baro Mano Worksheet

http://slidepdf.com/reader/full/baro-mano-worksheet 1/12

Name: …………………………… Unit: Pressure Worksheet******************************************************************************1. Stiletto heels can exert great pressure mainly due to a. the large force acting on it b. the small forceacting on itc. its large surface area d. its small surface

area

2. Which of the following places has the highest atmospheric pressure?a. on the top of a hill b. in a carc. on the roof top of a tall building d. at the bottom ofthe sea

3. Wind blows a. from areas of high atmospheric pressure to low pressure areasb. from areas of low atmospheric pressure to high pressure areas

c. only at areas above normal atmospheric pressured. only at areas below normal atmospheric pressure

. !he pressure in a li"uid decreases witha. increase in surface area b. decrease insurface areac. increase in depth d. decrease indepth

#. $ bloc% of wood measuring &m by 3m by '.#m is placed on a table. (f the mass

of the bloc% of wood is #''%g) what is the pressure on the table due to thebloc%? !a%e g*1'+,%g a. 2#''-a b. #'''-a c. '''-ad.22#''-a

&. $ man stands on snow wearing a pair of s%is. !he total mass of the man is&'%g and each of the s%is has an area of '.2m2 in contact with the snow. $ 1%gmass has a gravitational force of 1'+ acting on it. What pressure does the manexert on the snow?a. 1#+,m2 b. 3'+,m2 c. 1#''+,m2 d.3'''+,m2

/. Which of the following does not cause the height of the mercury column of asimple mercury barometer to vary?a. changes in atmospheric pressure b.changes in the value of gc. evaporation of mercury from the barometer reservoir d.lea%age of air into the tube

. (n which of the following examples is the greatest pressure exerted?a. a barefooted person standing on the beach b. abric% resting on the groundc. an elephant standing on the ground d. a%nife cutting a piece of meat



1'. $ tan% 3 m long) 1 m wide) and '.# m deep is 0lled with oil which weighs 12''' +. What is the pressure on the base of the tan% due to the oil?a. ''' -a b. &''' -a c. ''' -ad. 1 ''' -a

11. Water of depth 1'm exerts a pressure e"ual to atmospheric pressure. $n airbubble rises to the surface of a la%e which is 2'm deep. When the bubblereaches the surface) its volume is &cm3. What was the volume of the air bubbleat the bottom of the la%e?a. 2cm3 b. 3cm3 c. 12cm3 d.1cm3

12. $ rigid tan% containing air at atmospheric pressure has a capacity of #'''cm3. $ bicycle hand pump with a capacity of #''cm3 is used to pump more airinto the rigid container. iven that the hand pump is pumped twice to push twotubes of air into the tan%) what is the 0nal air pressure in the tan%? ta%eatmospheric pressure as 1'' ''' -a4a. 1'' ''' -a b. 12' ''' -a c. #'' ''' -a

d. 1 ''' ''' -a

13. 5xygen can be supplied to a 0sh tan% by bubbling air into the water. Whathappens to the pressure and the volume of air bubbles while they are rising? pressure volumea. decreases decreasesb. decreases increasesc. increases decreases

d. increases increases

1#. $ manometer contains water and a li"uid 6. !he two li"uids do not mix. !he pressure at level - in the water is e"ual to the pressure at level - in li"uid6. !he density of water is 1''' %g,m3. What is the density of li"uid 6?

a. #'' %g,m3

b. '' %g,m3

c. 12#' %g,m3

d. 2''' %g,m

1. !he 0gure shows a mercury barometer on a day when the atmospheric

pressure is /#'mm7g. What is the pressure at point 8) at the bottom of the

mercury reservoir?



2. !he 0gure shows a manometer with limbs of cross9sectional area of '.''1#m2.

(t contains a li"uid which exerts a pressure of #'''+m93. :alculate

i. the volume of li"uid between the levels -; and <S in the left9hand tube

ii. the weight of the volume of li"uid in i.

iii. the excess pressure) in +m92) of the gas supply above the surrounding

atmospheric pressure

3. When a bloc% of metal of mass 1.2%g stands on a hori=ontal surface) the area

of contact between the bloc% and the surface is .'cm2. $ssuming that the force

of gravity acting on a mass of 1%g is 1'+) calculate the pressure exerted by the

bloc% on the surface.

. !he 0gure shows a >9tube manometer connected to a gas cylinder of large

volume. !he atmospheric pressure is /&cm of mercury.

ai. What is the pressure at $ in the right9hand tube?

aii. What is the pressure at 8 in the left9hand tube?

b. !he tap is opened and mercury is run out until the level in the left9hand tube

drops to the &'cm mar%.

i. assuming that the pressure in the gas cylinder remains constant) what is the

new position of the level in the right9hand tube?

ii. xplain how you arrived at your answer.



#. !he 0gure shows two vertical tubes - and ;) each closed at the upper end.

!he pressure in the space above the mercury meniscus in tube - is negligibly

small. !here is a small amount of air in this space in the tube ;.

!he density of mercury is 13.& x 1' %g,m3. !he gravitational force on a mass of

1.''%g is 1'.'+.

@etermine

i. the atmospheric pressure) in -a) at that time.

ii. the pressure) in -a) exerted by the air in the space at the top of tube ;



&. !he tyres of a car are in contact with the ground over a total area 3.' x 1'92

m2. !he total weight of the car is &3''+. :alculate the pressure exerted by the

tyres on the ground.

Why would you expect the temperature of the tyres to have risen after the car

has been in motion for some time?

MCQ Questions

1. Stiletto heels can exert great pressure mainly due to

a. the large force acting on it

b. the small force acting on it

c. its large surface aread. its small surface area

2. Which of the following places has the highest atmospheric pressure?

a. on the top of a hill

b. in a cable car

c. on the roof top of a tall building

d. at the bottom of the sea

3. Wind blows

a. from areas of high atmospheric pressure to low pressure areasb. from areas of low atmospheric pressure to high pressure areas

c. only at areas above normal atmospheric pressure

d. only at areas below normal atmospheric pressure

4. The pressure in a liuid decreases with



a. increase in surface area

b. decrease in surface area

c. increase in depth

d. decrease in depth

!. " simple barometer filled with water has to ha#e a minimum length of

a. 1cm

b. 10cm

c. 10m

d. 100m

$. " bloc% of wood measuring $m by 3m by &.!m is placed on a table. 'f the mass of the bloc% of wood is 4!&&%g(

what is the pressure on the table due to the bloc%? ta%e gra#itational force acting on a mass of 1%g to be 1&)

a. 2500Pa

b. 5000Pa

c. 9000Pa

d.22500Pa

7. A man stands on snow wearing a pair of sis. !he total mass of the man is "0g and each of the sis has an area of

0.2m2

in contact with the snow. A 1g mass has a gravitational force of 10# acting on it. $hat pressure does the mane%ert on the snow&

a. 15#'m2

b. (0#'m2

c. 1500#'m2

d. (000#'m2

*. Which of the following does not cause the height of the mercury column of a simple mercury barometer to

#ary?

a. changes in atmospheric pressure

b. changes in temperature of the mercuryc. changes in the value of g

d. evaporation of mercury from the barometer reservoir

e. leaage of air into the tube

+. 'n which of the following examples is the greatest pressure exerted?

a. a barefooted person standing on the beach

b. a bric resting on the ground

c. a boo resting on a table

d. an elephant standing on the ground

e. a nife cutting a piece of meat

1&. " tan% 3 m long( 1 m wide( and &.! m deep is filled with oil which weighs 12 &&& ). What is the pressure on the

base of the tan% due to the oil?

a. )000 Pa

b. "000 Pa

c. *000 Pa

d. 1* 000 Pa

e. 2) 000 Pa

11. Water of depth 1&m exerts a pressure eual to atmospheric pressure. "n air bubble rises to the surface of a

la%e which is 2&m deep. When the bubble reaches the surface( its #olume is $cm3. What was the #olume of the air

bubble at the bottom of the la%e?

a. 2cm(

b. (cm(

c. 12cm(

d. 1*cm(



12. " rigid tan% containing air at atmospheric pressure has a capacity of !&&& cm3. " bicycle hand pump with a capacity of!&&cm3 is used to pump more air into the rigid container. ,i#en that the hand pump is pumped twice to push two tubes of airinto the tan%( what is the final air pressure in the tan%? -ta%e atmospheric pressure as 1&& &&& a/

a. 100 000 Pa

b. 120 000 Pa

c. 500 000 Pa

d. 1 000 000 Pa

13. 0xygen can be supplied to a fish tan% by bubbling air into the water. What happens to the pressure and the #olume of air

bubbles while they are rising?

pressure #olume

a. decreases decreases

b. decreases increases

c. increases decreases

d. increases increases

14. The rudder of a large ship is operated hydraulically. 0il at high pressure exerts a force on a piston that in turn mo#es a

le#er arm.

The oil is at a pressure of !&&%a and the surface area of the piston is &.2&m2. What is the sie of ?

a. 100#

b. 2500#

c. 100 000#

d. 250 000#

1!. " manometer contains water and a liuid . The two liuids do not mix. The pressure at le#el in the water is eual to the

pressure at le#el in liuid . The density of water is 1&&& %gm3. What is the density of liuid ?

a. 500 g'm(

b. *00 g'm(

c. 1250 g'm(

d. 2000 g'm(

+,- Answers

1. d

2. d



(. a

). d

5. c

". a

7. c

*. d

9. d

10. a

11. a

12. b

total vol of air at atm 5000 / 2 % 500 "000cm(

P11 100 000 % "000

ol of air in rigid container after pumping 2 tubes of air into it 5000cm(

P22 P2 % 5000

P11 P22

100 000 % "000 P2 % 5000

P2 120 000 Pa

1(. b

1). c

15. b

Structured Question Worked Solutions

1. The figure shows a mercury barometer on a day when the atmospheric pressure is 5!&mm6g. What is the

pressure at point 7( at the bottom of the mercury reser#oir?

Solution

Pressure 750 / *0 *(0 mm3g

2. The figure shows a manometer with limbs of cross8sectional area of &.&&1!m 2. 't contains a liuid which exerts

a pressure of !&&&)m83. 9alculate

i. the #olume of liuid between the le#els : and ;S in the left8hand tube

ii. the weight of the #olume of liuid in i.iii. the excess pressure( in )m 82( of the gas supply abo#e the surrounding atmospheric pressure



Solution

i. volume 0.0015 % 0.5 0.00075m(

ii. weight 0.00075 % 5000 (.75#

iii. pressure (.75'0.00015 2500#m42

3. When a bloc% of metal of mass 1.2%g stands on a horiontal surface( the area of contact between the bloc% and

the surface is *.&cm2. "ssuming that the force of gra#ity acting on a mass of 1%g is 1&)( calculate the pressure

exerted by the bloc% on the surface.

Solution

pressure force'area 1.2 % 10'* 1.5#m 42

4. The figure shows a <8tube manometer connected to a gas cylinder of large #olume. The atmospheric pressure is 5$cm of mercury.

ai. What is the pressure at " in the right8hand tube?

aii. What is the pressure at 7 in the left8hand tube?

b. The tap is opened and mercury is run out until the le#el in the left8hand tube drops to the $&cm mar%.

i. assuming that the pressure in the gas cylinder remains constant( what is the new position of the le#el in the right8hand tube?

ii. =xplain how you arri#ed at your answer.

Solution

ai. 7"cm3g. because A is e%posed to the atmosphere so it e%periences atmospheric pressure



aii. 10"cm3g because the pressure at e6uals the point in line with it in the other tube. !he pressure there is atmospheric pressure / pressure due to the column of mercury 7" / (0

bi. !he new position in the right4hand tube is at the (0cm mar

bii. !he pressure of the gas cylinder remains the same hence the difference between the levels of mercury in A and remains constant. 8ince drops by 20cm A liewise will drop by 20cm from the 10cm mar

to the (0cm mar.

!. The figure shows two #ertical tubes and :( each closed at the upper end. The pressure in the space abo#e

the mercury meniscus in tube is negligibly small. There is a small amount of air in this space in the tube :.

The density of mercury is 13.$ x 1& %gm3. The gra#itational force on a mass of 1.&&%g is 1&.&).

>etermine

i. the atmospheric pressure( in a( at that time.

ii. the pressure( in a( exerted by the air in the space at the top of tube :

Solution

i. Atmosphere pressure hpg 75.0'1001(." % 10(10.0 1.02 % 105 Pa

ii. air pressure at top of tube - atmospheric pressure 4 li6uid pressure due to "0.0cm of mercury

1.02 % 105 4 "0.0'1001(." % 10(10.0

2.0) % 10) Pa

$. The tyres of a car are in contact with the ground o#er a total area 3.& x 1& 82 m2. The total weight of the car is

$3&&). 9alculate the pressure exerted by the tyres on the ground.

Why would you expect the temperature of the tyres to ha#e risen after the car has been in motion for some time?

Solution

Pressure e%erted by the tyres weight'area "(00'(.0 % 1042 210 000 #'m2

!he temperature of the tyres rises because the wor done in overcoming friction with the road is transformed to heat energy



Applications of Atmospheric Pressure

(i) Drinking straw

When we suc% through a straw) the air pressure in the straw is

lowered. !hen the pressure of the atmosphere acting on thesurface of the drin% in the glass pushes the water up the strawand into our mouth.

(ii) Ruer sucker

When the suc%er is pressed into place) most of the air behind it is s"uee=ed out. !he suc%er is held in position by the pressure of atmosphere on the outside surface of the rubber. (f the seal between

the suc%er and the surface is airtight ) the suc%er will stic% permanently.

(iii) !"ringe

-ulling up the piston reduces the atmospheric pressure



inside the cylinder. !he atmospheric pressure on the li"uid surface then pushes the li"uid up into the syringe. (f we then hold the plunger in place and lift the syringe out of li"uid ) none will fall out.!his is again due to atmospheric pressure.

(iv)#acuum cleaner

$ vacuum cleaner produces only a partial vacuum.!he fan inside the cylinder blows air out of the vents.Which less air inside) the air pressure there drops.!he atmospheric pressure outside then pushes air upthe cleaner hose )carrying dust and dirt with it.

baro mano worksheet

Documents