Q: A hydraulic lift in an auto repair shop uses Pascal’s Principle to lift cars. If a mechanic applies a force of $$200\ \mathrm{N} to a $$piston with an area of $$0.01\ \mathrm{m}^2$$, what is the pressure transmitted to the fluid? (Assume no losses.)

$$2 \times 10^4$\ \mathrm{Pa}$$

Q: A diver descends to a depth of $$30\ \mathrm{m} in $$seawater ($$\rho = 1025\ \mathrm{kg/m}^3). $$What is the gauge pressure due to the water at this depth? (Use $$g = 9.8\ \mathrm{m/s}^2.)$$

$$3.0 \times 10^5$\ \mathrm{Pa}$$

Question 1

A hydraulic lift in an auto repair shop uses Pascal’s Principle to lift cars. If a mechanic applies a force of $$200\ \mathrm{N} to a $$piston with an area of $$0.01\ \mathrm{m}^2$$, what is the pressure transmitted to the fluid? (Assume no losses.)

Accepted Answer

$$2 	imes 10^4$\ \mathrm{Pa}$$

Question 2

A diver descends to a depth of $$30\ \mathrm{m} in $$seawater ($$\rho = 1025\ \mathrm{kg/m}^3). $$What is the gauge pressure due to the water at this depth? (Use $$g = 9.8\ \mathrm{m/s}^2.)$$

Accepted Answer

$$3.0 	imes 10^5$\ \mathrm{Pa}$$

Question 3

A block of wood with a density of $$600\ \mathrm{kg/m}^3$$ floats in water ($$\rho = 1000\ \mathrm{kg/m}^3). $$What fraction of the block’s volume is submerged?

Accepted Answer

$$0.60$$

Question 4

A $$5\ \mathrm{kg}$$ object is completely submerged in a liquid and experiences a buoyant force of $$40\ \mathrm{N}. $$What is the apparent weight of the object? (Use $$g = 9.8\ \mathrm{m/s}^2.)$$

Accepted Answer

$$9\ \mathrm{N}$$

Question 5

Which of the following best explains why a steel ship floats while a solid steel block of the same mass sinks?

Accepted Answer

The ship displaces more water, increasing the buoyant force.

Question 6

A sealed syringe is filled with water and has a small air bubble inside. If you push on the plunger, what happens to the pressure inside the syringe?

Accepted Answer

It increases equally throughout the syringe.

Question 7

A $$2\ \mathrm{kg}$$ block of aluminum and a $$2\ \mathrm{kg}$$ block of lead are both fully submerged in water. Which experiences the greater buoyant force?

Accepted Answer

The aluminum block

Question 8

A glass capillary tube is placed vertically in water. Which of the following changes will increase the height to which the water rises in the tube?

Accepted Answer

Decreasing the tube’s radius

Question 9

A soap bubble is spherical because:

Accepted Answer

Surface tension minimizes the surface area for a given volume.

Question 10

A person stands on a bathroom scale with both feet. If the person now stands on one foot, what happens to the pressure exerted on the scale?

Accepted Answer

It doubles.

Question 11

A submarine expels water from its ballast tanks while submerged. What happens to its density and position in the water?

Accepted Answer

Its density decreases and it rises.

Question 12

Which of the following statements about pressure in a liquid is correct?

Accepted Answer

Pressure at a given depth is independent of the container’s shape.

Question 13

A cook measures butter by placing it in a measuring cup with water and observing the water level rise. Which physical principle is being used?

Accepted Answer

The displacement rule

Question 14

A life preserver filled with lead pellets will:

Accepted Answer

Provide a greater buoyant force but still sink.

Question 15

Which of the following will decrease the surface tension of water?

Accepted Answer

Adding soap to the water

Question 16

A hot air balloon rises because:

Accepted Answer

It displaces a weight of air greater than its own weight.

Question 17

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

Accepted Answer

Energy output can exceed energy input in a hydraulic system.

Question 18

A capillary tube is placed in a liquid. Which combination will result in the highest capillary rise?

Accepted Answer

A narrow tube and a low-density liquid

Question 19

A $$1\ \mathrm{kg}$$ block of lead and a $$1\ \mathrm{kg}$$ block of aluminum are both submerged in water. Which experiences the greater buoyant force?

Accepted Answer

The aluminum block

Chapter 13: Liquids – Pressure, Buoyancy, and Fluid Principles

Guida di studio - Domande di pratica

Study guide - Flashcard