Q: A steel wrench has a mass of 0.6 kg and a volume of $$7.7 \times 10$$^{-5}$$ \ \mathrm{m}^3. $$What is its density?

$$7.8 \times 10^3$ \ \mathrm{kg/m}^3$$

Q: A diver is 20 meters below the surface of a freshwater lake. What is the absolute pressure at this depth? (Assume atmospheric pressure $$p_0 = 1.0$$ \times $$10^5$$ \ \mathrm{Pa}$$, $$\rho_{water} = 1.0 \times $$10^3$$ \ \mathrm{kg/m}^3$$, g = 9.8$$ \ \mathrm{m/s}^2$$)

$$2.96 \times 10^5$ \ \mathrm{Pa}$$

Question 1

A steel wrench has a mass of 0.6 kg and a volume of $$7.7 	imes 10$$^{-5}$$ \ \mathrm{m}^3. $$What is its density?

Accepted Answer

$$7.8 	imes 10^3$ \ \mathrm{kg/m}^3$$

Question 2

Which of the following best describes the pressure at a depth $$h in a $$fluid of uniform density $$\rho$$?

Accepted Answer

$$p = p_0$ + \rho g h$$

Question 3

A hydraulic lift uses a small piston of area $$0.01 \ \mathrm{m}^2$$ and a large piston of area $$0.5 \ \mathrm{m}^2. If a $$force of $$200 \ \mathrm{N} is $$applied to the small piston, what is the maximum weight that can be lifted by the large piston (neglecting friction)?

Accepted Answer

$$10,000 \ \mathrm{N}$$

Question 4

A diver is 20 meters below the surface of a freshwater lake. What is the absolute pressure at this depth? (Assume atmospheric pressure $$p_0 = 1.0$$ 	imes $$10^5$$ \ \mathrm{Pa}$$, $$ho_{water} = 1.0 	imes $$10^3$$ \ \mathrm{kg/m}^3$$, g = 9.8$$ \ \mathrm{m/s}^2$$)

Accepted Answer

$$2.96 	imes 10^5$ \ \mathrm{Pa}$$

Question 5

Which statement about gauge pressure is correct?

Accepted Answer

Gauge pressure is the difference between absolute pressure and atmospheric pressure.

Question 6

A block of wood with density $$0.6 	imes 10^3$ \ \mathrm{kg/m}^3$$ floats in water. What fraction of its volume is submerged?

Accepted Answer

$$0.6$$

Question 7

Which of the following best describes Archimedes's principle?

Accepted Answer

The buoyant force on an object is equal to the weight of the fluid displaced by the object.

Question 8

A water strider can walk on water due to which property of fluids?

Accepted Answer

Surface tension

Question 9

Which of the following is true about laminar and turbulent flow?

Accepted Answer

Laminar flow is characterized by smooth, parallel layers of fluid, while turbulent flow is chaotic and irregular.

Question 10

The continuity equation for an incompressible fluid flowing through a pipe is:

Accepted Answer

$$A_1$$ $$v_1$$ = $$A_2$$ $$v_2$$

Question 11

A pipe narrows from a cross-sectional area of $$0.05 \ \mathrm{m}^2 to$$ $$0.01 \ \mathrm{m}^2. If $$the speed of water in the wider section is $$2 \ \mathrm{m/s}$$, what is the speed in the narrower section?

Accepted Answer

$$10 \ \mathrm{m/s}$$

Question 12

Bernoulli's equation can be written as:

Accepted Answer

$$p_1$$ + \frac{1}{2} \rho $$v_1^2$$ + \rho g $$y_1$$ = $$p_2$$ + \frac{1}{2} \rho $$v_2^2$$ + \rho g $$y_2$$

Question 13

Why do airplane wings generate lift according to Bernoulli's principle?

Accepted Answer

Air moves faster over the top of the wing, creating lower pressure above than below.

Question 14

A Venturi meter measures the flow speed of a fluid by comparing:

Accepted Answer

The pressure difference between two points of different cross-sectional area.

Question 15

Which of the following statements about viscosity is correct?

Accepted Answer

Viscosity is a measure of a fluid's internal friction.

Question 16

Lava flows more easily when it is hotter because:

Accepted Answer

Its viscosity decreases with increasing temperature.

Question 17

A patient’s blood pressure is measured as 120/80 mm Hg. What does the 120 mm Hg represent?

Accepted Answer

The maximum gauge pressure in the arteries (systolic pressure).

Question 18

Why is listening for turbulent flow in the human aorta with a stethoscope a useful diagnostic technique?

Accepted Answer

Turbulent flow produces audible noise, which can indicate abnormal blood flow.

Question 19

Which of the following is NOT a correct consequence of Pascal’s law?

Accepted Answer

Pressure applied to a fluid decreases with depth.

Question 20

Which of the following best explains why the pressure at the bottom of connected columns of fluid is the same, regardless of the shape of the columns?

Accepted Answer

Pressure at a given depth depends only on the height of the fluid column, not its shape.

Chapter 12: Fluid Mechanics – Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards