Deck 9: Fluids

Question 1

Atmospheric pressure is 1.013 × 10⁵ N/m². The pressure of the atmosphere in pounds/in² is

A) 9.800 lb/in².
B) 10.90 lb/in².
C) 12.30 lb/in².
D) 14.70 lb/in².
E) 16.30 lb/in².

Answer 1

14.70 lb/in².

Question 2

A force of 120.0 N is applied to 2.000 cm diameter piston, which is in contact with a closed container of water (density of water = 1,000 kg/m³). A second piston, with a diameter of 25.00 cm and at the same height as the first piston, is also in contact with the water. What force does the water pressure exert on the second piston?

A) 18,750 N.
B) 10,450 N.
C) 9,500 N.
D) 9,150 N.
E) 8,450 N.

Answer 2

18,750 N.

Question 3

Mercury has a density of 13,600 kg/m³. The height of a column of mercury that would produce a pressure of 1.013 × 10⁵ N/m² is

A) 32.1 in.
B) 29.9 in.
C) 25.4 in.
D) 19.8 in.
E) 9.80 in.

Answer 3

29.9 in.

Question 4

A submarine is at a depth of 500 m under the water. The force on a circular hatch of diameter 1.00 m due to the seawater (density = 1,025 kg/m³) pressure from outside the submarine is

A) 2.45 × 10⁶ N.
B) 4.02 × 10⁶ N.
C) 3.94 × 10⁶ N.
D) 5.50 × 10⁶ N.
E) 6.34 × 10⁶ N.

Question 5

The water level in a water tower is 50.00 m above the ground. What is the gauge pressure of the water at a faucet that is 2.000 m above the ground?

A) 500,200 N/m²
B) 470,400 N/m²
C) 451,300 N/m²
D) 422,400 N/m²
E) 410,400 N/m²

Question 6

The difference in blood pressure between the head and the foot of a person who is 2.00 m tall and resting on an incline that is at an angle of 30.0 degrees to the horizontal is (density of blood is 1,060 kg/m³)

A) 59.8 mmHg.
B) 62.8 mmHg.
C) 68.6 mmHg.
D) 70.2 mmHg.
E) 77.9 mmHg.

Question 7

The water level in a water tower is 50 m above the ground. What is the gauge pressure of the water at a faucet that is 20 m above the ground?

A) 1.8 atm
B) 1.9 atm
C) 2.1 atm
D) 2.5 atm
E) 2.9 atm

Question 8

What is the density of a mixture of 90% air (density air 1.20 kg/m³) and 10% helium (density of 0.180 kg/m³)?

A) 0.680 kg/m³
B) 0.750 kg/m³
C) 0.980 kg/m³
D) 1.098 kg/m³
E) 1.103 kg/m³

Question 9

A 100 kg mass has a density of 2,000 kg/m³. If the volume is decreased by 2% due to compression, then the density is

A) 3,011 kg/m³.
B) 2,940 kg/m³.
C) 2,522 kg/m³.
D) 2,440 kg/m³.
E) 2,041 kg/m³.

Question 10

A container has a large cylindrical lower part with a long thin cylindrical neck. The lower part of the container holds 12.5 m³ of water and the surface area of the bottom of the container is 5.00 m². The height of the lower part of the container is 2.50 m and the neck contains a column of water 8.50 m high. The total volume of the column of water in the neck is 0.200 m³. What is the magnitude of the force exerted by the water on the bottom of the container?

A) 1.65 × 10⁶ N
B) 1.05 × 10⁶ N
C) 1.15 × 10⁶ N
D) 1.35 × 10⁶ N

Question 11

The cork in a bottle is 2.00 cm in diameter. If the pressure inside the bottle is 3.00 atm, then the net force on the cork due to the pressure difference is

A) 37.5 N.
B) 45.5 N.
C) 48.9 N.
D) 55.3 N.
E) 63.6 N.

Question 12

The foot pedal on hydraulic brake system exerts a force of 45 lb on a piston with a diameter of 1.00 cm. The brake fluid in the brake system exerts the pressure from the foot pedal on a brake pad piston with a diameter of 2.50 cm. The force on the brake pad is

A) 133 lb.
B) 150 lb.
C) 281 lb.
D) 350 lb.
E) 402 lb.

Question 13

The car lift in a gas station operates with an air pressure of 2,000 kPa. The piston of the car lift has a diameter of 30.0 cm. What is the mass of the largest car that the lift can raise?

A) 8,750 kg
B) 9,450 kg
C) 10,300 kg
D) 14,400 kg
E) 17,500 kg

Question 14

A submarine is located 2.000 km below the surface of the water. What is the absolute pressure of the seawater on the outside of the submarine? (density of seawater is 1,025 kg/m³)

A) 175.0 atm
B) 187.3 atm
C) 199.3 atm
D) 205.5 atm
E) 210.0 atm

Question 15

Water has a density of 1,000 kg/m³. The height of a column of water that would produce a pressure of 1.013 × 10⁵ N/m² is

A) 7.330 m.
B) 9.820 m.
C) 10.34 m.
D) 15.72 m.
E) 20.01 in.

Question 16

The difference in blood pressure between the head and the foot of a person who is 2.00 m tall and standing up is (density of blood is 1,060 kg/m³)

A) 156 mmHg.
B) 142 mmHg.
C) 126 mmHg.
D) 102 mmHg.
E) 198 mmHg.

Question 17

What is the density of a mixture of 85% air (density air 1.20 kg/m³) and 15% water vapor (density of water vapor 0.600 kg/m³)?

A) 1.70 kg/m³
B) 1.87 kg/m³
C) 1.05 kg/m³
D) 1.11 kg/m³
E) 1.19 kg/m³

Question 18

A hydraulic lift has a small piston with a diameter 5.0 cm piston and the large piston with a diameter of 25 cm. What force must be applied to the small piston in order to lift a car on the large piston that weighs 13,000 N?

A) 520 N
B) 5,200 N
C) 260 N
D) 2,600 N

Question 19

A submarine is located 1.000 km below the surface of the water. What is the absolute pressure of the seawater on the outside of the submarine? (density of seawater is 1,025 kg/m³)

A) 190.8 atm
B) 193.5 atm
C) 198.2 atm
D) 100.1 atm
E) 121.2 atm

Question 20

Atmospheric pressure is 1.013 × 10⁵ N/m². The pressure of the atmosphere in kPa is

A) 101.3 kPa.
B) 98.10 kPa.
C) 75.40 kPa.
D) 66.70 kPa.
E) 55.20 kPa.

Question 21

A 10.0 kg ball weighs 98.0 N in air and weighs 65.0 N when submerged in water. The volume of the ball is

A) 0.00337 m³.
B) 0.00457 m³.
C) 0.00766 m³.
D) 0.00980 m³.
E) 0.00245 m³.

Question 22

Water is flowing through a pipe with a constriction. The area of the narrow section is one-half the area of the wide section. If the velocity of the incompressible fluid is 3.2 m/s in the narrow section, then what is the velocity of the fluid in the wide section?

A) 0.9 m/s
B) 1.0 m/s
C) 1.6 m/s
D) 1.8 m/s
E) 1.9 m/s

Question 23

An incompressible fluid is flowing through a horizontal pipe with a constriction. The velocity of the fluid in the wide section of the pipe is 6.00 m/s and the velocity of the fluid in the narrow section of pipe is 8.00 m/s. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 183 kPa
B) 236 kPa
C) 268 kPa
D) 285 kPa
E) 298 kPa

Question 24

A mercury manometer measures a pressure of 150 mmHg. What is this pressure in kPa?

A) 12 kPa
B) 15 kPa
C) 20 kPa
D) 24 kPa
E) 29 kPa

Question 25

A 90.0 kg scuba diver with tanks and equipment is submerged and floating underwater in seawater (density 1.025 g/cm3). The volume of the seawater displaced by the scuba diver with tanks and equipment is

A) 0.0508 m³.
B) 0.0575 m³.
C) 0.0667 m³.
D) 0.0708 m³.
E) 0.0878 m³.

Question 26

What is the buoyant force on a 1.200 kg solid steel ball submerged in water? (density of steel is 7,900 kg/m³)

A) 1.136 N
B) 1.245 N
C) 1.489 N
D) 1.566 N
E) 1.750 N

Question 27

A mercury manometer measures a pressure of 200 mmHg. What is this pressure in atm?

A) 0.204 atm
B) 0.263 atm
C) 0.301 atm
D) 0.325 atm
E) 0.375 atm

Question 28

A 1.10 kg hollow steel ball is submerged in water. Its weight in water is 8.75 N. The volume of the cavity inside the ball is (density of steel is 7,900 kg/m³)

A) 1.59 × 10⁻⁵ m³.
B) 6.79 × 10⁻⁵ m³.
C) 1.13 × 10⁻⁴ m³.
D) 1.39 × 10⁻⁴ m³.
E) 2.07 × 10⁻⁴ m³.

Question 29

A ball with a diameter of 20.00 cm is placed in water with 75% of its volume above the surface of the water. The buoyant force of the water on the ball is

A) 16.67 N.
B) 14.75 N.
C) 13.60 N.
D) 12.56 N.
E) 10.26 N.

Question 30

An incompressible fluid is flowing through a horizontal pipe with a constriction. The velocity of the fluid in the wide section of the pipe is 5.00 m/s and the velocity of the fluid in the narrow section of pipe is 8.00 m/s. The pressure of the fluid in the wide section is 200 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 680 kg/m³)

A) 155 kPa
B) 160 kPa
C) 175 kPa
D) 187 kPa
E) 207 kPa

Question 31

A 1.50 kg hollow steel ball is submerged in water. Its weight in water is 10.75 N. The volume of the cavity inside the ball is (density of steel is 7,900 kg/m³)

A) 0.000139 m³.
B) 0.000213 m³.
C) 0.000348 m³.
D) 0.000401 m³.
E) 0.000476 m³.

Question 32

A 10 kg ball weighs 98 N in air and weighs 75 N when submerged in water. The upward buoyant force on the ball is

A) 32 N.
B) 30 N.
C) 24 N.
D) 23 N.
E) 19 N.

Question 33

Water is flowing through a pipe with a constriction. The area of the narrow section is one-half the area of the wide section. If the velocity of the incompressible fluid is 3.2 m/s in the wide section, then what is the velocity of the fluid in the narrow section?

A) 6.4 m/s
B) 5.9 m/s
C) 5.0 m/s
D) 4.7 m/s
E) 4.2 m/s

Question 34

A ball with a diameter of 10.0 cm is submerged in water. The buoyant force of the water on the ball is

A) 4.25 N.
B) 4.75 N.
C) 5.13 N.
D) 5.75 N.
E) 6.00 N.

Question 35

Water is flowing through a pipe with a constriction. The diameter of the narrow section is one-half the diameter of the wide section. If the velocity of the incompressible fluid is 3.20 m/s in the wide section, then what is the velocity of the fluid in the narrow section?

A) 16.5 m/s
B) 18.7 m/s
C) 19.8 m/s
D) 10.5 m/s
E) 12.8 m/s

Question 36

Water is flowing through a pipe with a constriction. The diameter of the narrow section is one-third the diameter of the wide section. If the velocity of the incompressible fluid is 3.6 m/s in the narrow section, then what is the velocity of the fluid in the wide section?

A) 2.00 m/s
B) 0.80 m/s
C) 1.4 m/s
D) 1.0 m/s
E) 0.40 m/s

Question 37

A 1.5 kg ball is floating in water. The volume of water displaced by the ball is

A) 0.0015 m³.
B) 0.0027 m³.
C) 0.0036 m³.
D) 0.0040 m³.
E) 0.0051 m³.

Question 38

A 120 kg scuba diver with tanks and equipment is submerged and floating underwater in seawater (density 1.025 g/cm3). The volume of the seawater displaced by the scuba diver with tanks and equipment is

A) 0.097 m³.
B) 0.102 m³.
C) 0.117 m³.
D) 0.154 m³.
E) 0.177 m³.

Question 39

A 2 kg ball is floating in water. The volume of water displaced by the ball is

A) 0.005 m³.
B) 0.004 m³.
C) 0.003 m³.
D) 0.002 m³.
E) 0.001 m³.

Question 40

A mercury manometer measures a pressure of 200.0 mmHg. What is this pressure in Pa?

A) 19,770 Pa
B) 26,660 Pa
C) 30,230 Pa
D) 36,760 Pa
E) 39,600 Pa

Question 41

An incompressible fluid is flowing through a vertical pipe with a constriction. The wide section is 2.00 cm in diameter and is at the top of the pipe. The pressure of the fluid in the wide section at the top is 200 kPa. The velocity of the fluid in the wide section is 4.00 m/s. The narrow section is located 2.00 m below the wide section. What is the diameter of the narrow section, if the pressure of the fluid in the narrow section is equal to the pressure in the wide section? (density of the fluid is 1,000 kg/m³)

A) 1.47 cm
B) 1.20 cm
C) 1.10 cm
D) 0.90 cm
E) 0.75 cm

Question 42

An incompressible fluid is flowing through a pipe with a constriction. The pipe is on an incline with an angle of 20.0 degrees. The narrow section is 15.0 m from the wide section and the narrow section is higher than the wide section. The velocity of the fluid in the wide section of the pipe is 6.00 m/s and the velocity of the fluid in the narrow section of pipe is 9.00 m/s. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 217 kPa
B) 205 kPa
C) 180 kPa
D) 177 kPa
E) 157 kPa

Question 43

An incompressible fluid is flowing through a pipe with a constriction. The pipe is on an incline with an angle of 30.0 degrees. The narrow section is 10.0 m from the wide section and the narrow section is lower than the wide section. The velocity of the fluid in the wide section of the pipe is 2.00 m/s and the velocity of the fluid in the narrow section of pipe is 10.0 m/s. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 175 kPa
B) 199 kPa
C) 212 kPa
D) 245 kPa
E) 251 kPa

Question 44

An incompressible fluid is flowing through a pipe with a constriction. The pipe is on an incline with an angle of 30.0 degrees. The narrow section is 10.0 m from the wide section and the narrow section is higher than the wide section. The velocity of the fluid in the wide section of the pipe is 4.00 m/s. The diameter of the wide section is 12.00 cm and the diameter of the narrow section is 9.00 cm. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 210 kPa
B) 205 kPa
C) 195 kPa
D) 184 kPa
E) 175 kPa

Question 45

An incompressible fluid is flowing through a pipe with a constriction. The pipe is on an incline with an angle of 30.0 degrees from the horizontal. The narrow section is 10.0 m from the wide section and the narrow section is higher than the wide section. The velocity of the fluid in the wide section of the pipe is 4.00 m/s and the velocity of the fluid in the narrow section of pipe is 9.00 m/s. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 169 kPa
B) 175 kPa
C) 180 kPa
D) 193 kPa
E) 205 kPa

Question 46

An incompressible fluid is flowing through a vertical pipe with a constriction. The wide section is 2.00 cm in diameter and is at the top of the pipe. The pressure of the fluid in the wide section at the top is 200 kPa. The velocity of the fluid in the wide section is 4.00 m/s. The narrow section is located 8.00 m below the wide section. What is the diameter of the narrow section, if the pressure of the fluid in the narrow section is equal to the pressure in the wide section? (density of the fluid is 680 kg/m³)

A) 1.10 cm
B) 1.20 cm
C) 1.31 cm
D) 1.42 cm
E) 1.55 cm

Question 47

An incompressible fluid is flowing through a vertical pipe with a constriction. The wide section is 2.00 cm in diameter and is at the top of the pipe. The pressure of the fluid in the wide section at the top is 200 kPa. The velocity of the fluid in the wide section is 4.00 m/s. The narrow section is 1.00 cm in diameter and is located 2.00 m below the wide section. What is the pressure of the fluid in the narrow section? (density of the fluid is 1,000 kg/m³)

A) 72.0 kPa
B) 80.0 kPa
C) 99.6 kPa
D) 105 kPa
E) 116 kPa

Question 48

An incompressible fluid is flowing through a pipe with a constriction. The pipe is on an incline with an angle of 30.0 degrees. The narrow section is 15.0 m from the wide section and the narrow section is lower than the wide section. The velocity of the fluid in the wide section of the pipe is 4.00 m/s and the velocity of the fluid in the narrow section of pipe is 9.00 m/s. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 260 kPa
B) 275 kPa
C) 291 kPa
D) 301 kPa
E) 320 kPa

Question 49

A small hole is cut in the bottom of a water storage tank. The depth of the water is 12.00 m. If the diameter of the small hole in the bottom of the tank is 4.00 mm, then what is the flow rate of the water leaving the tank?

A) 1.05 × 10⁻⁴ m³/s
B) 1.36 × 10⁻⁴ m³/s
C) 1.93 × 10⁻⁴ m³/s
D) 2.53 × 10⁻⁴ m³/s
E) 2.65 × 10⁻⁴ m³/s

Question 50

The surface tension of soapy water is 0.0250 N/m. What is the height of the water in a capillary tube of diameter 2.00 mm?

A) 5.10 mm
B) 4.77 mm
C) 4.21 mm
D) 3.98 mm
E) 3.66 mm

Question 51

An incompressible fluid is flowing through a horizontal pipe with a constriction. The velocity of the fluid in the wide section of the pipe is 4.00 m/s and the velocity of the fluid in the narrow section of pipe is 9.00 m/s. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 218 kPa
B) 225 kPa
C) 237 kPa
D) 246 kPa
E) 252 kPa

Question 52

Glycerin at 30°C has a density of 1,260 kg/m³ and a viscosity of 0.630 Pa s. In a laboratory experiment, some glycerin is forced through a horizontal tube that is 10.0 cm long and 1.00 cm in diameter. The high-pressure end of the tube is held at a gauge pressure of 618 Pa, while the other end is open to the atmosphere. What is the flow rate of the glycerin through the tube?

A) 1.70 × 10⁻⁶ m³/s
B) 1.87 × 10⁻⁶ m³/s
C) 1.95 × 10⁻⁶ m³/s
D) 2.05 × 10⁻⁶ m³/s
E) 2.41 × 10⁻⁶ m³/s

Question 53

An incompressible fluid is flowing through a vertical pipe with a constriction. The wide section is 2.00 cm in diameter and is at the top of the pipe. The pressure of the fluid in the wide section at the top is 200 kPa. The velocity of the fluid in the wide section is 4.00 m/s. The narrow section is located 4.00 m below the wide section. What is the diameter of the narrow section , if the pressure of the fluid in the narrow section is equal to the pressure in the wide section? (density of the fluid is 680 kg/m³)

A) 1.50 cm
B) 1.43 cm
C) 1.36 cm
D) 1.28 cm
E) 1.15 cm

Question 54

An incompressible fluid is flowing through a horizontal pipe with a constriction. The velocity of the fluid in the wide section of the pipe is 5.00 m/s. The diameter of the wide section is 10.0 cm and the diameter of the narrow section is 8.00 cm. The pressure of the fluid in the wide section is 200 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 680 kg/m³)

A) 188 kPa
B) 175 kPa
C) 160 kPa
D) 152 kPa
E) 148 kPa

Question 55

The surface tension of water is 0.0730 N/m. What is the height of the water in a capillary tube of diameter 1.00 mm?

A) 3.02 cm
B) 2.98 cm
C) 2.75 cm
D) 2.55 cm
E) 2.40 cm

Question 56

An incompressible fluid is flowing through a pipe with a constriction. The pipe is on an incline with an angle of 20.0 degrees. The narrow section is 15.0 m from the wide section and the narrow section is lower than the wide section. The velocity of the fluid in the wide section of the pipe is 6.00 m/s and the velocity of the fluid in the narrow section of pipe is 9.00 m/s. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 278 kPa
B) 228 kPa
C) 195 kPa
D) 167 kPa
E) 145 kPa

Question 57

The surface tension of water is 0.0730 N/m. What is the height of the water in a capillary tube of diameter 2.00 mm?

A) 1.27 cm
B) 1.37 cm
C) 1.49 cm
D) 1.58 cm
E) 1.63 cm

Question 58

A small hole is cut in the bottom of a water storage tank. The depth of the water is 8.00 m. If the diameter of the small hole in the bottom of the tank is 1.00 cm, then what is the flow rate of the water leaving the tank?

A) 9.83 × 10⁻⁴ m³/s
B) 8.75 × 10⁻⁴ m³/s
C) 8.21 × 10⁻⁴ m³/s
D) 7.45 × 10⁻⁴ m³/s
E) 7.21 × 10⁻⁴ m³/s

Question 59

An incompressible fluid is flowing through a pipe with a constriction. The pipe is on an incline with an angle of 30.0 degrees. The narrow section is 10.0 m from the wide section and the narrow section is lower than the wide section. The velocity of the fluid in the wide section of the pipe is 4.00 m/s. The diameter of the wide section is 12.00 cm and the diameter of the narrow section is 9.00 cm. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1,000 kg/m³)

A) 295 kPa
B) 282 kPa
C) 275 kPa
D) 252 kPa
E) 240 kPa

Question 60

An incompressible fluid is flowing through a vertical pipe with a constriction. The wide section is 2.00 cm in diameter and is at the top of the pipe. The pressure of the fluid in the wide section at the top is 200 kPa. The velocity of the fluid in the wide section is 4.00 m/s. The narrow section is located 4.00 m below the wide section. What is the diameter of the narrow section for the pressure of the fluid in the narrow section to equal the pressure in the wide section? (density of the fluid is 1,000 kg/m³)

A) 1.50 cm
B) 1.36 cm
C) 1.28 cm
D) 1.12 cm
E) 1.00 cm

Question 61

A wooden ball is tied to the bottom of a swimming pool by a string. What is the tension in the string if the ball's diameter is 0.15 m and its mass is 144 g? The water in the pool is fresh water, density 1,000 kg/m³.

A) 15.9 N
B) 12.7 N
C) 14.1 N
D) 1.78 N

Question 62

Water undergoes viscous flow through two pipes with the same pressure difference between the ends. Pipe 1 has three times the diameter and twice the length of pipe 2. If the flow rate through pipe 1 is 0.400 cm³/s, then what is the flow rate through pipe 2?

A) 6.22 × 10⁻³ cm³/s
B) 7.78 × 10⁻³ cm³/s
C) 8.33 × 10⁻³ cm³/s
D) 9.88 × 10⁻³ cm³/s
E) 10.80 × 10⁻³ cm³/s

Question 63

A 2525 kg truck can be held up by a piston of radius 15 cm through a hydraulic lift by a force of 175 N on a piston of what radius?

A) 3.9 cm
B) 1.04 cm
C) 1.06 cm
D) 1.26 cm

Question 64

You would like to drink water through a straw that is 12 cm long, held vertically. The atmospheric pressure is standard, 101.3 kPa. With one end of the straw just inside your mouth, and the other just beneath the water surface, what maximum pressure inside your mouth would enable you to drink the water? Ignore viscosity.

A) 94.5 kPa
B) 102.5 kPa
C) 100.1 kPa
D) 89.5 kPa

Question 65

A viscous fluid is flowing through a small tube at a rate of 2.0 × 10⁻⁴ m³/s. If the pressure difference between the ends of the tube is doubled and the radius is also doubled, then what is the new rate of flow of the fluid?

A) 6.4 × 10⁻³ m³/s
B) 5.6 × 10⁻³ m³/s
C) 4.4 × 10⁻³ m³/s
D) 3.7 × 10⁻³ m³/s
E) 2.6 × 10⁻³ m³/s

Question 66

The pressure at what depth in seawater (density 1,025 kg/m³) is equivalent to that at a depth of 10.0 m in fresh water (density 1,000 kg/m³)?

A) 10.2 m
B) 9.76 m
C) 10.3 m
D) 9.81 m

Question 67

Air with a density of 1.20 kg/m³ flows through a 75.0 cm diameter pipe with a velocity of 2.00 m/s. What is the mass flow rate?

A) 0.95 kg/s
B) 1.06 kg/s
C) 1.20 kg/s
D) 1.26 kg/s
E) 1.48 kg/s

Question 68

The pressure at a depth of 1.25 m in a tank of liquid is measured to be 125.5 kPa. The tank is open to the outside air, which is at a pressure of 102.0 kPa. What is the density of the fluid?

A) 1,920 kg/m³
B) 10,200 kg/m³
C) 18,800 kg/m³
D) 2,400 kg/m³

Question 69

Water with a density of 1,000 kg/m³ flows through a 2.00 cm diameter pipe with a velocity of 2.40 m/s. What is the volume flow rate?

A) 5.43 × 10⁻⁴ m³/s
B) 6.24 × 10⁻⁴ m³/s
C) 7.54 × 10⁻⁴ m³/s
D) 8.14 × 10⁻⁴ m³/s
E) 9.00 × 10⁻⁴ m³/s

Question 70

In an attempt to avoid "the bends", which occurs if a diver rises too quickly after having been at great depth in the ocean for a long period of time, a diver should come to the surface relatively slowly. What would the rate of change (in Pa/s) of the water pressure be on a diver in the ocean as he rose at 15 m/min? The density of seawater is 1,017 kg/m³.

A) 15 kPa/s
B) 2.5 kPa/s
C) 250 Pa/s
D) 150 kPa/s

Question 71

A baseball (0.145 kg, circumference 229 mm) is held completely underwater in the ocean (density of seawater 1,017 kg/m³). What force is required to hold the baseball in place?

A) 0.600 N
B) 0.490 N
C) It requires no additional force to remain completely submerged.
D) 0.061 N
E) 0.145 N

Question 72

Water with a density of 1,000 kg/m³ flows through a 4.00 cm diameter pipe with a velocity of 1.20 m/s. What is the mass flow rate?

A) 1.01 kg/s
B) 1.21 kg/s
C) 1.32 kg/s
D) 1.40 kg/s
E) 1.51 kg/s

Question 73

A ball naturally floats with 35% of its volume above the surface of a pool filled with mercury (density 13,600 kg/m³). If a force of 1,200 N is required to force the ball completely under water, what is the radius of the ball?

A) 5.7 cm
B) 18.3 cm
C) 14.9 cm
D) 12.9 cm

Question 74

A small steel sphere falls with terminal velocity of 2.00 cm/s in a viscous fluid. If the radius of the steel sphere is doubled, what will the new terminal velocity of the sphere be?

A) 1.00 cm/s
B) 2.00 cm/s
C) 4.00 cm/s
D) 6.00 cm/s
E) 8.00 cm/s

Question 75

A viscous fluid is flowing through a small tube at a rate of 0.400 m3/s. If the pressure difference across the tube is tripled and the length of the tube is doubled, and the radius is also doubled, then what is the new rate of flow of the fluid?

A) 9.6 m³/s
B) 10.2 m³/s
C) 12.00 m³/s
D) 14.2 m³/s
E) 15.5 m³/s

Question 76

Water flows in a flexible tube of radius 1.5 cm at the floor level of a house. The tube is joined to a second tube of smaller radius (1.2 cm), which runs to a floor 7.2 m above. If the pressure in the lower tube is 214 kPa, and the pressure in the upper tube is 107 kPa, what is the speed of water in the upper (smaller radius) tube?

A) 8.9 m/s
B) 4.5 m/s
C) 13.9 m/s
D) 11.1 m/s

Question 77

A sphere of radius 25 cm rests at the bottom of a pool containing fresh water, completely submerged. If the upward normal force on the sphere from the bottom of the pool is 1,025 N, what is the mass of the sphere?

A) 38 kg
B) 39 kg
C) 65 kg
D) 105 kg
E) 170 kg

Question 78

A viscous fluid is flowing through a small tube at a rate of 0.200 m3/s. If the pressure difference across the tube is doubled, and the length of the tube is halved, and the radius is also doubled, then what is the new rate of flow of the fluid?

A) 9.2 m³/s
B) 10.2 m³/s
C) 12.8 m³/s
D) 13.4 m³/s
E) 14.6 m³/s

Question 79

What is the force on the top surface of a 10.5 cm-diameter soup can that is submerged in seawater (density 1,017 kg/m³) at a depth of 350 m? The air pressure at the surface is 101.5 kPa.

A) 30.2 kN
B) 31.1 kN
C) 124 kN
D) 121 kN

Question 80

Air with a density of 1.20 kg/m³ flows through a 10.0 cm diameter pipe with a velocity of 1.20 m/s. What is the mass flow rate?

A) 0.0148 kg/s
B) 0.0131 kg/s
C) 0.0120 kg/s
D) 0.0113 kg/s
E) 0.0098 kg/s