Question 1

In order to overcome a surface tension of a fluid,a force of 1.34 × 10−² N is required to lift a wire ring of circumference 12.0 cm.What is the surface tension of the fluid?

Accepted Answer

Surface tension = Force required to lift the wire ring / Circumference of the wire ring= 1.34 × 10−² N / 12.0 cm= 0.056 N/m

Question 2

The condition for onset of turbulent flow is that the Reynolds Number reaches what value?

Accepted Answer

The critical Reynolds Number for onset of turbulent flow is typically around 3,000. Therefore, the correct option is C, which is 3,000. Options A, B, and D are incorrect.

Question 3

A container is filled with water and the pressure at the container bottom is P.If the container is instead filled with oil having specific gravity 0.80,what new bottom pressure results?

Accepted Answer

The pressure at the bottom of a container filled with a fluid is given by $P = \rho gh$, where $\rho$ is the density of the fluid, $g$ is the acceleration due to gravity, and $h$ is the height of the fluid column. Since oil has a lower density than water (specific gravity of 0.80 means the oil's density is 80% that of water), the pressure at the bottom of the container when filled with oil will be less than when it is filled with water.

Question 4

Which of the following characterizes the net force on a particle falling through a fluid at its terminal speed?

Accepted Answer

When a particle is falling through a fluid at its terminal speed, the fluid resistance force experienced by the particle is equal and opposite to the weight of the particle. This means that the net force on the particle is zero, and thus the particle falls at a constant velocity called the terminal speed.

Question 5

A fluid has a density of 1 040 kg/m³.If it rises to a height of 1.6 cm in a 1.5-mm diameter capillary tube,what is the surface tension of the liquid? Assume a contact angle of zero.

Accepted Answer

The surface tension of the liquid can be calculated using the formula:$$P = \frac{2\gamma \cos 	heta}{r}$$where:* P is the pressure difference between the inside and outside of the capillary tube* γ is the surface tension of the liquid* θ is the contact angle between the liquid and the capillary tube* r is the radius of the capillary tubeIn this case, the pressure difference is equal to the hydrostatic pressure of the liquid column, which is given by:$$P = ho g h$$where:* ρ is the density of the liquid* g is the acceleration due to gravity* h is the height of the liquid columnSubstituting these values into the first equation, we get:$$ho g h = \frac{2\gamma \cos 	heta}{r}$$Solving for γ, we get:$$\gamma = \frac{ho g h r}{2\cos 	heta}$$Substituting the given values, we get:$$\gamma = \frac{(1040 	ext{ kg/m}^3)(9.81 	ext{ m/s}^2)(1.6 	imes 10^{-2} 	ext{ m})}{2\cos 0^\circ}$$$$\gamma = 0.061 	ext{ N/m}$$Therefore, the correct answer is A.

Question 6

Water is sent from a fire hose at 35 m/s at an angle of 30° above the horizontal.What is the maximum height reached by the water?

Accepted Answer

The vertical component of the velocity is $ v_{y} = 35 \sin(30°) = 17.5 \, \text{m/s} $. Using the formula for maximum height $ h = \frac{v_{y}^2}{2g} $, where $ g = 9.8 \, \text{m/s}^2 $, we get $ h = \frac{(17.5)^2}{2 \times 9.8} \approx 15.625 \, \text{m} $, which rounds to 16 m.

Question 7

How much power is theoretically available from a mass flow of 1 200 kg/s of water that falls a vertical distance of 110 m?

Accepted Answer

The theoretical power available from falling water can be calculated using the formula:
P = mgh, where P is power, m is mass flow, g is the acceleration due to gravity, and h is the vertical distance.
Plugging in the values, we get:
P = 1200 x 9.81 x 110 = 1,294,680 W
Converting to kW, we get:
P = 1294.68 kW
Therefore, the best choice is A, 1,294 kW.

Question 8

Spherical particles of density 1.6 g/cm³ are shaken in a container of water (viscosity = 1.0 × 10−³ N⋅s/m³).The water is 10.0 cm deep and is allowed to stand for 35 minutes.What is the radius of the largest particles still in suspension at that time?

Accepted Answer

The answer of Spherical particles of density 1.6 g/cm³ are...

Question 9

Spherical particles of density 2.0 g/cm³ are shaken in a container of water (viscosity = 1.0 × 10−³ N⋅s/m³).The water is 7.0 cm deep and is allowed to stand for 30 minutes.What is the greatest terminal velocity of the particles still in suspension at that time?

Accepted Answer

The answer of Spherical particles of density 2.0 g/cm³ are...

Question 10

An ice cube with a small solid steel sphere frozen inside floats in a glass of water filled to the brim.What happens to the level of water in the glass as a result of the ice melting?

Accepted Answer

The answer of An ice cube with a small solid...

Question 11

At a pressure of 1 atmosphere a column of mercury in a barometer is supported to the height h = 0.76 m.The density of mercury is 13.6 × 10³ kg/m³.A barometer of similar design filled with water would support a column of water how high at a pressure of 1 atmosphere?

Accepted Answer

The answer of At a pressure of 1 atmosphere a...

Question 12

Water is being sprayed from a nozzle at the end of a garden hose of diameter 2.0 cm.If the nozzle has an opening of diameter 1.0 cm,and if the water leaves the nozzle at a speed of 12 m/s,what is the speed of the water inside the hose?

Accepted Answer

The speed of the water inside the hose is less than the speed of the water leaving the nozzle because the water is being constricted as it passes through the nozzle. The ratio of the speeds is equal to the ratio of the areas of the hose and the nozzle, so the speed of the water inside the hose is:v_hose = v_nozzle * (A_nozzle / A_hose)v_hose = 12 m/s * (1.0 cm / 2.0 cm)^2v_hose = 3 m/s

Question 13

It takes 2.5 minutes to fill a gas tank with 50 liters of gasoline.If the pump nozzle is 2.0 cm in radius,what is the average speed of the gasoline as it leaves the nozzle? (1 000 liters = one cubic meter)

Accepted Answer

We can use the equation for the flow rate of a liquid through a circular opening: Q = Av, where Q is the flow rate, A is the cross-sectional area of the opening, and v is the velocity of the liquid. We know that the volume of gasoline that flows through the nozzle in 2.5 minutes is 50 L = 0.05 m^3. We can convert the radius of the nozzle from cm to m: r = 0.02 m. The cross-sectional area of the opening is then A = πr^2 = 1.2566 x 10^-3 m^2. Using the given time and volume, we can find the flow rate: Q = 0.05 m^3 / 2.5 min = 0.00083333... m^3/s. Solving for v, we get v = Q / A = 0.6628... m/s. Rounding to one significant figure gives v = 0.7 m/s, which is closest to choice B, 0.3 m/s.

Question 14

A centrifuge rotates at 100 rev/s (i.e. ,628 rad/s).If the test tube places the suspension at 8.0 cm from the axis of rotation,by what factor are the terminal speeds of the settling particles increased as compared to sedimentation cause by gravity?

Accepted Answer

The centrifugal acceleration is given by a = ω²r, where ω = 628 rad/s and r = 0.08 m. The acceleration due to gravity is g = 9.8 m/s². The factor increase is a/g = (628² * 0.08) / 9.8 ≈ 3.2 × 10³.

Question 15

A container is filled with water and the pressure at the bottom of the container is P.Then the container is emptied halfway and topped off with oil of density 0.8 × 10³ kg/m³,which floats on top of the water.What is the pressure at the bottom of the container now?

Accepted Answer

The answer of A container is filled with water and...

Question 16

A pipe carrying water has a radius of 1.0 cm.If the flow velocity is 9.0 cm/s,which of the following characterizes the flow? Take the viscosity of water to be 1.0 × 10−³ N⋅s/m.

Accepted Answer

The flow is characterized by the Reynolds number, Re = (density × velocity × diameter) / viscosity. For water, density is approximately 1000 kg/m³. Converting units and calculating, Re = (1000 kg/m³ × 0.09 m/s × 0.02 m) / (1.0 × 10^-3 N⋅s/m²) = 1800. Since Re < 2000, the flow is streamlined (laminar).

Question 17

When an artery gets a constricted region due to plaque,how does the pressure in this region compare to the pressure in an unconstricted region adjacent?

Accepted Answer

According to Bernoulli's principle, when the velocity of a fluid increases, its pressure decreases. In the constricted region of an artery, blood moves at a higher speed compared to the unconstricted region, leading to a decrease in pressure.

Question 18

A pipe of diameter four cm is replaced by one of the same length but of diameter twelve cm.If the pressure difference between the ends of the pipe remains the same,by what factor is the rate of flow of a viscous liquid through it changed?
​

Accepted Answer

The rate of flow of a viscous liquid through a pipe is proportional to the fourth power of the diameter (Poiseuille's Law). If the diameter increases from 4 cm to 12 cm, the factor change in flow rate is (12/4)^4 = 3^4 = 81.

Quiz 9: Solids and Fluids

In order to overcome a surface tension of a fluid,a force of 1.34 × 10−² N is required to lift a wire ring of circumference 12.0 cm.What is the surface tension of the fluid?

The condition for onset of turbulent flow is that the Reynolds Number reaches what value?

A container is filled with water and the pressure at the container bottom is P.If the container is instead filled with oil having specific gravity 0.80,what new bottom pressure results?

Which of the following characterizes the net force on a particle falling through a fluid at its terminal speed?

A fluid has a density of 1 040 kg/m³.If it rises to a height of 1.6 cm in a 1.5-mm diameter capillary tube,what is the surface tension of the liquid? Assume a contact angle of zero.

Water is sent from a fire hose at 35 m/s at an angle of 30° above the horizontal.What is the maximum height reached by the water?

How much power is theoretically available from a mass flow of 1 200 kg/s of water that falls a vertical distance of 110 m?

Spherical particles of density 1.6 g/cm³ are shaken in a container of water (viscosity = 1.0 × 10−³ N⋅s/m³) .The water is 10.0 cm deep and is allowed to stand for 35 minutes.What is the radius of the largest particles still in suspension at that time?

Spherical particles of density 2.0 g/cm³ are shaken in a container of water (viscosity = 1.0 × 10−³ N⋅s/m³) .The water is 7.0 cm deep and is allowed to stand for 30 minutes.What is the greatest terminal velocity of the particles still in suspension at that time?

An ice cube with a small solid steel sphere frozen inside floats in a glass of water filled to the brim.What happens to the level of water in the glass as a result of the ice melting?

At a pressure of 1 atmosphere a column of mercury in a barometer is supported to the height h = 0.76 m.The density of mercury is 13.6 × 10³ kg/m³.A barometer of similar design filled with water would support a column of water how high at a pressure of 1 atmosphere?

Water is being sprayed from a nozzle at the end of a garden hose of diameter 2.0 cm.If the nozzle has an opening of diameter 1.0 cm,and if the water leaves the nozzle at a speed of 12 m/s,what is the speed of the water inside the hose?

It takes 2.5 minutes to fill a gas tank with 50 liters of gasoline.If the pump nozzle is 2.0 cm in radius,what is the average speed of the gasoline as it leaves the nozzle? (1 000 liters = one cubic meter)

A centrifuge rotates at 100 rev/s (i.e. ,628 rad/s) .If the test tube places the suspension at 8.0 cm from the axis of rotation,by what factor are the terminal speeds of the settling particles increased as compared to sedimentation cause by gravity?

A container is filled with water and the pressure at the bottom of the container is P.Then the container is emptied halfway and topped off with oil of density 0.8 × 10³ kg/m³,which floats on top of the water.What is the pressure at the bottom of the container now?

A pipe carrying water has a radius of 1.0 cm.If the flow velocity is 9.0 cm/s,which of the following characterizes the flow? Take the viscosity of water to be 1.0 × 10−³ N⋅s/m.

When an artery gets a constricted region due to plaque,how does the pressure in this region compare to the pressure in an unconstricted region adjacent?

A pipe of diameter four cm is replaced by one of the same length but of diameter twelve cm.If the pressure difference between the ends of the pipe remains the same,by what factor is the rate of flow of a viscous liquid through it changed?

Quiz 9: Solids and Fluids

In order to overcome a surface tension of a fluid,a force of 1.34 × 10−2 N is required to lift a wire ring of circumference 12.0 cm.What is the surface tension of the fluid?

The condition for onset of turbulent flow is that the Reynolds Number reaches what value?

A container is filled with water and the pressure at the container bottom is P.If the container is instead filled with oil having specific gravity 0.80,what new bottom pressure results?

Which of the following characterizes the net force on a particle falling through a fluid at its terminal speed?

A fluid has a density of 1 040 kg/m3.If it rises to a height of 1.6 cm in a 1.5-mm diameter capillary tube,what is the surface tension of the liquid? Assume a contact angle of zero.

Water is sent from a fire hose at 35 m/s at an angle of 30° above the horizontal.What is the maximum height reached by the water?

How much power is theoretically available from a mass flow of 1 200 kg/s of water that falls a vertical distance of 110 m?

Spherical particles of density 1.6 g/cm3 are shaken in a container of water (viscosity = 1.0 × 10−3 N⋅s/m3) .The water is 10.0 cm deep and is allowed to stand for 35 minutes.What is the radius of the largest particles still in suspension at that time? ​

Spherical particles of density 2.0 g/cm3 are shaken in a container of water (viscosity = 1.0 × 10−3 N⋅s/m3) .The water is 7.0 cm deep and is allowed to stand for 30 minutes.What is the greatest terminal velocity of the particles still in suspension at that time? ​

An ice cube with a small solid steel sphere frozen inside floats in a glass of water filled to the brim.What happens to the level of water in the glass as a result of the ice melting?

At a pressure of 1 atmosphere a column of mercury in a barometer is supported to the height h = 0.76 m.The density of mercury is 13.6 × 103 kg/m3.A barometer of similar design filled with water would support a column of water how high at a pressure of 1 atmosphere?

Water is being sprayed from a nozzle at the end of a garden hose of diameter 2.0 cm.If the nozzle has an opening of diameter 1.0 cm,and if the water leaves the nozzle at a speed of 12 m/s,what is the speed of the water inside the hose?

It takes 2.5 minutes to fill a gas tank with 50 liters of gasoline.If the pump nozzle is 2.0 cm in radius,what is the average speed of the gasoline as it leaves the nozzle? (1 000 liters = one cubic meter)

A centrifuge rotates at 100 rev/s (i.e. ,628 rad/s) .If the test tube places the suspension at 8.0 cm from the axis of rotation,by what factor are the terminal speeds of the settling particles increased as compared to sedimentation cause by gravity?

A container is filled with water and the pressure at the bottom of the container is P.Then the container is emptied halfway and topped off with oil of density 0.8 × 103 kg/m3,which floats on top of the water.What is the pressure at the bottom of the container now?

A pipe carrying water has a radius of 1.0 cm.If the flow velocity is 9.0 cm/s,which of the following characterizes the flow? Take the viscosity of water to be 1.0 × 10−3 N⋅s/m.

When an artery gets a constricted region due to plaque,how does the pressure in this region compare to the pressure in an unconstricted region adjacent?

A pipe of diameter four cm is replaced by one of the same length but of diameter twelve cm.If the pressure difference between the ends of the pipe remains the same,by what factor is the rate of flow of a viscous liquid through it changed? ​

In order to overcome a surface tension of a fluid,a force of 1.34 × 10−² N is required to lift a wire ring of circumference 12.0 cm.What is the surface tension of the fluid?

A fluid has a density of 1 040 kg/m³.If it rises to a height of 1.6 cm in a 1.5-mm diameter capillary tube,what is the surface tension of the liquid? Assume a contact angle of zero.

Spherical particles of density 1.6 g/cm³ are shaken in a container of water (viscosity = 1.0 × 10−³ N⋅s/m³) .The water is 10.0 cm deep and is allowed to stand for 35 minutes.What is the radius of the largest particles still in suspension at that time?

Spherical particles of density 2.0 g/cm³ are shaken in a container of water (viscosity = 1.0 × 10−³ N⋅s/m³) .The water is 7.0 cm deep and is allowed to stand for 30 minutes.What is the greatest terminal velocity of the particles still in suspension at that time?

At a pressure of 1 atmosphere a column of mercury in a barometer is supported to the height h = 0.76 m.The density of mercury is 13.6 × 10³ kg/m³.A barometer of similar design filled with water would support a column of water how high at a pressure of 1 atmosphere?

A container is filled with water and the pressure at the bottom of the container is P.Then the container is emptied halfway and topped off with oil of density 0.8 × 10³ kg/m³,which floats on top of the water.What is the pressure at the bottom of the container now?

A pipe carrying water has a radius of 1.0 cm.If the flow velocity is 9.0 cm/s,which of the following characterizes the flow? Take the viscosity of water to be 1.0 × 10−³ N⋅s/m.

A pipe of diameter four cm is replaced by one of the same length but of diameter twelve cm.If the pressure difference between the ends of the pipe remains the same,by what factor is the rate of flow of a viscous liquid through it changed?