Physics of Gases and Liquids: Conceptual Questions and Problems

These flashcards cover key questions and concepts related to the properties of gases and liquids as discussed in the lecture notes.

Why are gases easier to compress than liquids and solids?

Gases have larger spaces between molecules, allowing for easier compression.

How do gases and liquids differ?

Gases have no definite shape or volume, while liquids have a definite volume but take the shape of their container.

How is pressure related to the sharpness of a knife and its ability to cut?

Higher pressure from a sharp knife allows for easier penetration into materials.

Why does a dull hypodermic needle hurt more than a sharp one?

A dull needle exerts lower pressure, requiring more force and causing more tissue damage.

How is the outward force on one end of an air tank balanced?

The force is balanced by an equal and opposite force acting on the other end of the tank.

Which ice chunk would give the greatest increase in lake water level when melted: iceberg or glacier?

The iceberg would give a greater increase in water level as it is already floating.

Will the same ship float higher in salt water than in freshwater?

Yes, a ship floats higher in salt water because salt water is denser.

What is the volume of 1 troy ounce of pure gold?

The volume of 1 troy ounce of pure gold is approximately 1.09 cubic centimeters.

What is the volume in liters of 34.5 kg of mercury?

The volume is approximately 25.8 liters, as mercury's density is 13.6 g/cm³.

Identify some substances that are incompressible and some that are not.

Liquids (e.g., water) are generally incompressible, while gases (e.g., air) are compressible.

How does placing your thumb over a garden hose affect the water flow?

It increases the pressure in the hose, allowing the water to be squirted farther when released.

Why does water broaden as it rises in a fountain and narrow when falling from a faucet?

The broadening is due to reduced pressure at higher altitudes, while narrowing occurs due to acceleration towards the ground.

What is the average flow rate of gasoline to a car at 100 km/h averaging 10.0 km/L?

The average flow rate is 100 cm³/s.

What is the speed of blood through the aorta with a flow rate of 5.0 L/min and a radius of 1.0 cm?

The speed of blood is approximately 0.64 m/s.

Estimate the time to fill an 80,000 L swimming pool at 60 L/min.

It would take approximately 1,333 minutes or about 22.2 hours.

How long to fill the pool using a river flowing at 5000 m³/s?

It would take approximately 0.048 seconds.

Verify that pressure has units of energy per unit volume.

Pressure is defined as force per unit area; energy per unit volume can be represented as force times distance divided by volume.

What will the pitot tube reading be at 700 km/h if it was 15.0 mm Hg at 200 km/h?

The pressure reading would increase based on the square of the speed ratio, needing calculation to determine exact value.