Most Important Fluid Dynamics Quiz Test Online

Fluid Dynamics Quiz Test Online

Fluid Dynamics Test. 1

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1) A large ship made of steel floats, while a small steel bolt sinks. This is because the ship:

Has a smaller mass-to-volume ratio than the bolt

Is hollow, making it lighter than water

Is less dense than the bolt

Has a shape that displaces a large volume of water

The ship's hollow hull displaces a huge volume of water, generating a buoyant force large enough to support its total weight.

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2) A river flows from a wide section into a narrow gorge. According to the equation of continuity, the speed of the water in the narrow gorge will:

Increase

Decrease

Remain the same

Become turbulent

To maintain a constant flow rate (Av), a decrease in area (A) must be compensated by an increase in velocity (v).

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3) A steel wire and a rubber band of the same length and cross-sectional area are subjected to the same stretching force. Which one will have a higher Young's Modulus?

The rubber band

It cannot be determined without knowing the extension

The steel wire

They will have the same Young's Modulus

Steel resists deformation much more than rubber. A high Young's Modulus indicates a material is very stiff and requires large stress for a small strain.

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4) A force of 500 N is applied to a wire with a cross-sectional area of 2 × 10⁻⁶ m². What is the tensile stress on the wire?

250 Pa

1 × 10⁻³ Pa

4 × 10⁻⁹ Pa

2.5 × 10⁸ Pa

Stress is calculated as Force divided by Area. The calculation is 500 N / (2 × 10⁻⁶ m²) = 2.5 × 10⁸ Pa.

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5) A fluid is considered 'ideal' for simplifying calculations. Which of the following is NOT a property of an ideal fluid?

The flow is irrotational

The fluid is incompressible

The fluid is viscous

The flow is steady

An ideal fluid is assumed to be non-viscous, meaning there is no internal friction between its layers.

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6) What does the area under a force-extension graph represent for a material deformed within its elastic limit?

Tensile Strength

Elastic Potential Energy

Spring Constant

Young's Modulus

The work done to stretch the material is stored as elastic potential energy, which is represented by the area under the force-extension graph.

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7) According to Bernoulli's principle, if the speed of a fluid increases, what happens to its internal pressure?

It increases

It remains constant

It depends on the fluid's viscosity

It decreases

Bernoulli's equation shows an inverse relationship between speed and pressure to conserve total energy.

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8) A Venturi meter is used to measure the speed of a fluid in a pipe. It works by measuring the:

Height difference of the entire pipe

Change in the fluid's viscosity

Temperature change in a constricted section

Pressure difference between a wide and a narrow section

The pressure drop in the narrow (high-velocity) section is directly related to the fluid's speed, which is the operating principle of the device.

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9) The lift on an airplane wing is primarily generated by a pressure difference. Where is the pressure lower?

The pressure is the same on both surfaces

On the top surface of the wing

On the bottom surface of the wing

At the leading edge of the wing

The curved top surface forces air to travel faster, which, by Bernoulli's principle, creates a region of lower pressure.

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10) What is the point on a stress-strain curve beyond which a material will not return to its original shape after the stress is removed?

Fracture Point

Elastic Limit

Proportional Limit

Ultimate Tensile Strength

This is the correct term for the maximum stress a material can withstand without undergoing permanent (plastic) deformation.

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11) An object falling through a fluid reaches terminal velocity when:

The drag force becomes equal to its weight

The upthrust equals its weight

It stops accelerating

The force of gravity on it is zero

When the upward drag force perfectly balances the downward force of weight, the net force is zero, and acceleration stops.

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12) Which type of fluid flow is characterized by smooth, parallel layers where particles follow the same path as preceding particles?

Viscous Flow

Turbulent Flow

Streamline Flow

Compressible Flow

This is the definition of streamline or laminar flow, where fluid motion is orderly and predictable.

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13) According to Archimedes' principle, the upward buoyant force on a submerged object is equal to the:

Mass of the object

Weight of the object in air

Weight of the fluid displaced by the object

Volume of the fluid displaced by the object

This is the correct definition of Archimedes' principle. The upthrust equals the weight of the displaced fluid.

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14) Which of these materials is an example of an amorphous or glassy solid?

Sodium Chloride

Glass

Copper

Diamond

Glass is the archetypal amorphous solid; its molecules are arranged randomly, without long-range order.

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15) Strain is defined as the fractional change in a property. What are the SI units of tensile strain?

It is dimensionless

Meters (m)

Newtons (N)

Pascals (Pa)

Since strain is a ratio of two lengths (ΔL/L₀), the units (e.g., meters) cancel out, making it a dimensionless quantity.

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16) Which of the following solids is characterized by a regular, repeating arrangement of atoms or molecules throughout its structure?

Polymeric Solid

Glassy Solid

Amorphous Solid

Crystalline Solid

Crystalline solids are defined by their long-range, ordered atomic structure, which forms a crystal lattice.

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17) A gardener puts a thumb over the end of a hose to make the water spray farther. This action demonstrates:

Pascal's Law

Bernoulli's Principle

The Equation of Continuity

Archimedes' Principle

By reducing the cross-sectional area (A), the velocity (v) of the water must increase to maintain a constant flow rate.

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18) A submarine increases its weight by filling its ballast tanks with seawater. It will begin to sink when:

It displaces a volume of water equal to its own volume

Its weight becomes greater than the upthrust

Its weight is equal to the upthrust

Its weight is less than the upthrust

For an object to sink, the downward force of its weight must overcome the upward buoyant force (upthrust).

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19) The equation of continuity (A₁v₁ = A₂v₂) is a direct consequence of which fundamental principle?

Conservation of Momentum

Conservation of Mass

Conservation of Energy

Newton's Third Law

The equation states that for an incompressible fluid, the mass entering a section of pipe in a given time must equal the mass leaving it.

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20) The retarding force experienced by an object moving through a fluid is known as:

Weight

Terminal Force

Drag Force

Upthrust

This is the correct term for the frictional, retarding force a fluid exerts on a moving object.

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Fluid Dynamics Test. 2

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1) A spinning baseball curves in the air (a curveball). This is an example of the Magnus effect, which is explained by Bernoulli's principle. The ball curves because:

Pressure is higher where spin opposes airflow

The spin increases the ball's weight

The spin makes one side of the ball heavier than the other

The air has zero viscosity, allowing the ball to curve

The side spinning with the airflow has faster-moving air (lower pressure), while the side spinning against the airflow has slower air (higher pressure), creating a net force.

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2) If the terminal velocity of a spherical raindrop of radius 'r' is 'v', what would be the approximate terminal velocity of a spherical raindrop of radius '2r' (assuming all other factors are constant)?

v/2

The formula vₜ = (2ρgr²)/(9η) shows that terminal velocity is proportional to the square of the radius (r²). If r is doubled, vₜ increases by a factor of 2²=4.

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3) The property of a body to return to its original shape and size after the removal of a deforming force is called:

Brittleness

Ductility

Elasticity

Plasticity

This is the definition of elasticity, the ability to recover from deformation.

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4) A paratrooper jumps from a plane. They reach a terminal velocity, then open their parachute and reach a new, lower terminal velocity. Why is the second terminal velocity lower?

The force of gravity is weaker closer to the ground

The parachute increases the surface area and drag force

The density of the air increases significantly

The paratrooper's mass decreases

A much larger drag force means that the balance with weight occurs at a much lower speed.

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5) Blood flows from the aorta (large radius) into many smaller arteries. For the total flow rate to remain constant, the speed of the blood in the smaller arteries is:

Slower than in the aorta

Faster than in the aorta

Zero

The same as in the aorta

The aorta has a smaller total area (A₁) than the sum of all the branching arteries (A₂). By A₁v₁ = A₂v₂, if A₂ > A₁, then v₂ must be less than v₁.

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6) The transition from laminar to turbulent flow occurs when:

The fluid's velocity exceeds critical speed

The fluid's viscosity remains constant

The fluid's velocity decreases

The fluid becomes incompressible

Above a critical speed, the smooth, layered flow breaks down into chaotic, irregular motion.

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7) Substances that undergo significant plastic deformation before they break, such as copper, are known as:

Brittle substances

Elastic substances

Ductile substances

Amorphous substances

This is the correct term for materials that can be stretched, bent, or drawn into a wire without breaking.

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8) For a horizontal pipe of varying cross-section, Bernoulli's equation simplifies to P + (1/2)ρv² = constant. Why is the ρgh term not present?

The fluid is assumed to be massless

The pressure is constant in a horizontal pipe

Gravity is ignored in fluid dynamics

The pipe is horizontal, so the height (h) is constant

If the height does not change (h₁ = h₂), the potential energy term (ρgh) is the same on both sides of the equation and can be cancelled out.

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9) Torricelli's theorem (v = √(2gh)) calculates the speed of efflux from an orifice in a tank. This speed is equivalent to the speed an object would have after:

Being thrown upwards with an initial velocity v

Sliding down a frictionless ramp of height h

Falling freely from a height h

Being submerged to a depth h

This theorem is a special case of Bernoulli's equation where the potential energy of the fluid at height h is converted into kinetic energy at the orifice.

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10) Bernoulli's equation (P + (1/2)ρv² + ρgh = constant) is an expression of:

Momentum conservation per unit volume

Force conservation per unit volume

Energy conservation per unit volume

Mass conservation per unit volume

Each term in the equation represents a form of energy per unit volume: pressure (work energy), kinetic energy, and potential energy.

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11) Hooke's Law states that stress is directly proportional to strain. In which region of the stress-strain curve is this law obeyed?

The entire elastic region

The fracture point

The proportional limit region

The plastic region

This is the specific region where the relationship is linear, which is the essence of Hooke's Law.

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12) Which property of a fluid is a measure of its internal friction or resistance to flow?

Surface Tension

Viscosity

Compressibility

Density

This is the definition of viscosity. High viscosity means high resistance to flow (like honey), while low viscosity means it flows easily (like water).

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13) In the context of blood flow, arteriosclerosis (narrowing of the arteries) can be dangerous. According to Bernoulli's principle, the pressure inside a narrowed section of an artery is:

The same as in the wider sections, but the blood moves faster

Lower than in the surrounding, wider sections

Dependent only on the heart's pumping force

Higher than in the surrounding, wider sections

To maintain flow, blood speeds up in the narrowed region (continuity). This higher speed results in lower internal pressure, which can cause the artery to collapse or dislodge plaque.

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14) A spring with a spring constant of k = 400 N/m is stretched by 0.2 m. How much elastic potential energy is stored in the spring?

40 J

8 J

16 J

80 J

The correct formula is Eₚ = (1/2)kx². The calculation is 0.5 × 400 × (0.2)² = 8 J.

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15) According to Stokes' Law, the drag force on a small sphere is directly proportional to all of the following EXCEPT:

The density of the fluid (ρ)

The radius of the sphere (r)

The viscosity of the fluid (η)

The velocity of the sphere (v)

Stokes' law for drag force depends on viscosity, not density. Density is used when calculating terminal velocity, where weight is involved.

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16) What is a key characteristic of a superfluid?

Zero viscosity

Extremely high temperature

Solid crystalline structure

Infinite density

This is the defining characteristic. A superfluid can flow without any internal friction or loss of kinetic energy.

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17) A perfume bottle atomizer works by blowing a fast stream of air across the top of a tube dipped in the perfume. This causes the perfume to rise and spray out because the fast-moving air has:

High pressure, which pushes the liquid up

Low density, which creates a vacuum

Low pressure, which pushes the liquid up

High viscosity, which pulls the liquid up

The low pressure created by the fast air stream allows the higher atmospheric pressure on the liquid's surface in the bottle to push it up the tube.

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18) The principle of flotation states that a floating object displaces a weight of fluid equal to:

Its own weight

Its own volume

The weight of the container

Half its own weight

The buoyant force, which equals the weight of the displaced fluid, must be equal to the object's total weight for it to float.

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19) A hot-air balloon rises because:

Its total weight is less than the weight of the air it displaces.

The balloon's fabric is lighter than air

Heating the air removes its mass

The pressure inside the balloon is greater than the pressure outside

The buoyant force from the displaced ambient air is greater than the total weight of the balloon, which is an application of the principle of flotation.

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20) A wooden cube with a volume of 0.01 m³ is fully submerged in water (density ≈ 1000 kg/m³). What is the buoyant force acting on it? (Use g ≈ 9.8 m/s²)

98 N

9.8 N

0.98 N

10 N

Buoyant force = (density of fluid) x (volume displaced) x g. The calculation is 1000 × 0.01 × 9.8 = 98 N.

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Fluid Dynamics Test. 3

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1) If a fluid is incompressible, it means that its ________ is constant.

Viscosity

Density

Pressure

Velocity

This is the definition of an incompressible fluid – its mass per unit volume does not change under pressure.

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2) Shear stress is a type of stress that causes a change in the ________ of a body.

Mass

Shape

Volume

Length

Shear stress involves forces applied parallel to a surface, causing one layer of the material to slide relative to another, thus changing its shape.

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3) Which of the following describes plastic deformation?

A permanent change in shape that remains after the deforming force is removed.

A material that returns to its original shape when a force is removed.

A material that breaks immediately when force is applied.

A deformation that is directly proportional to the applied force.

This is the correct definition of plastic deformation, occurring after the elastic limit has been exceeded.

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4) Which of the following is a polymer solid?

Wool

Glass

Copper

Sodium Chloride

Wool is a natural polymer, composed of long-chain protein molecules.

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5) In the derivation of Bernoulli's equation, what form of energy is represented by the term P (pressure)?

Internal Thermal Energy

Kinetic Energy

Work done by the fluid per unit volume

Gravitational Potential Energy

Pressure is force per unit area. In the context of the energy equation, it represents the work done on or by the fluid element per unit volume.

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6) If a stone is submerged in water and weighs less than it does in air, this phenomenon is due to:

The gravitational force acting upward

A reduction of the stone's mass in water

The buoyant force acting upwards

An increase in the density of water

The upward buoyant force counteracts some of the downward gravitational force, resulting in a lower apparent weight.

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7) The effect of a decrease of pressure with an increase in the speed of a fluid in a horizontal pipe is called:

Torricelli's effect

Doppler's effect

Venturi's effect

Bernoulli's effect

This is the name given to the principle that an increase in a fluid's speed occurs simultaneously with a decrease in pressure.

8 / 20

8) What happens to the coefficient of viscosity of a gas as its temperature increases?

It becomes zero

It decreases

It remains constant

It increases

In gases, viscosity arises from molecular collisions. Higher temperature means more frequent and energetic collisions, which increases the resistance to flow.

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9) Which of the following is the most elastic?

Steel

Sponge

Wood

Rubber

In physics, 'elasticity' refers to the ability to resist deformation. Steel has a very high Young's Modulus, making it extremely elastic.

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10) In Searle's apparatus for determining Young's modulus, a reference wire is used alongside the test wire. What is the primary purpose of this reference wire?

To ensure the support is strong enough

To compensate for changes in temperature

To double the amount of extension measured

To hold the micrometer screw gauge

Any thermal expansion or contraction will affect both wires equally, so the measurement of extension due to the load remains accurate.

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11) The flow rate of a fluid is given as 2 m³/s through a pipe with a cross-sectional area of 0.5 m². What is the velocity of the fluid?

4 m/s

0.25 m/s

1 m/s

2.5 m/s

Flow rate = Area x Velocity. Therefore, Velocity = Flow rate / Area. The calculation is 2 / 0.5 = 4 m/s.

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12) What happens to the coefficient of viscosity of a liquid as its temperature increases?

It increases

It decreases

It remains constant

It becomes zero

Increased thermal energy overcomes the intermolecular cohesive forces, reducing the liquid's resistance to flow.

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13) A water tank has a small hole 5 m below the surface. Using Torricelli's theorem, what is the exit speed of the water? (Use g ≈ 9.8 m/s²)

9.9 m/s

49 m/s

7 m/s

2.2 m/s

The formula is v = √(2gh). The calculation is √(2 × 9.8 × 5) ≈ 9.9 m/s.

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14) An ideal flow of a fluid must satisfy:

Stokes' Law

Both Bernoulli's and continuity equations

Bernoulli's equation

The equation of continuity

An ideal fluid flow must conserve both mass (continuity) and energy (Bernoulli), so both equations must be satisfied.

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15) The lift force experienced by an airplane wing is primarily due to:

The pressure difference above and below wing

The viscosity of the air

The density of the air

The gravitational force acting on the air

This is the fundamental reason for lift, as explained by Bernoulli's principle.

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16) Young's modulus has the same SI unit as which other quantity?

Energy

Stress

Force

Strain

Young's modulus is the ratio of stress (in Pascals) to strain (dimensionless). Therefore, its units are the same as stress, Pascals (Pa) or N/m².

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17) Why does smoke from an incense stick rise in a smooth, laminar flow at first, but then become chaotic and turbulent farther up?

Smoke cools and gets denser

Air becomes less viscous higher up

Speed increases, causing turbulence

Gravity has less effect on it as it rises

The hot, less dense smoke accelerates upwards. As its velocity increases, it crosses the threshold from laminar to turbulent flow.

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18) Which of these materials would be considered brittle?

Lead

High-carbon steel

Wrought iron

Polythene

High-carbon steel is hard but brittle. It will fracture soon after its elastic limit is reached, unlike more ductile low-carbon steel.

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19) Why is it dangerous to stand too close to a fast-moving train?

The fast-moving air creates low pressure pushing you towards the train.

The ground vibrates, causing you to lose your balance.

The wind generated by the train can be strong enough to blow you over.

The train creates a high-pressure zone that pushes you away.

This is a classic real-world example of Bernoulli's effect. The higher pressure of the stationary air behind you pushes you into the low-pressure region created by the train.

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20) A Venturi mask, used in the medical field to deliver a known oxygen concentration, operates based on:

Pascal's law

Newton's third law

Bernoulli's principle

Archimedes' principle

A fast jet of oxygen creates a low-pressure zone that entrains a predictable amount of ambient air, which is an application of Bernoulli's principle.

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Fluid Dynamics Test. 4

1 / 20

1) In a solid, cohesive forces are the intermolecular forces that:

Bind similar molecules to one another.

Cause the solid to flow like a liquid.

Hold the solid to the walls of its container.

Are only present in crystalline solids.

Cohesion is the attraction between like molecules, responsible for holding a substance together.

2 / 20

2) Which instrument is used to measure the diameter of a thin wire accurately in an experiment to find Young's Modulus?

Screw gauge

Spirit level

Vernier caliper

Meter rule

A screw gauge (or micrometer) is designed to measure very small dimensions like the diameter of a wire with high precision.

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3) When you hold a piece of paper under your bottom lip and blow over the top, the paper rises. This demonstrates:

The Bernoulli effect.

The Archimedes effect.

The Coanda effect.

The Magnus effect.

The fast-moving air you blow over the top of the paper creates a low-pressure zone, and the higher pressure of the still air underneath pushes the paper up.

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4) The term 'efflux' refers to:

The buoyant force on an object.

The pressure at the bottom of a container.

The flowing out of a fluid from a container.

The mixing of two different fluids.

This is the correct definition, as used in Torricelli's theorem for the 'speed of efflux'.

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5) The ultimate tensile strength (UTS) of a material represents the:

Stress at which the material breaks.

Point where stress is no longer proportional to strain.

Maximum stress the material can withstand before starting to weaken.

Stress at which the material returns to its original shape.

UTS is the peak of the stress-strain curve, after which the material begins to 'neck' and weaken.

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6) When a fluid flows through a horizontal pipe, the pressure is lowest where the fluid's speed is:

Lowest

Highest

Constant

Zero

This is a direct application of Bernoulli's principle for a horizontal pipe.

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7) If the radius of a pipe is halved, to keep the flow rate constant, the velocity of the fluid must:

Increase by a factor of 4

Increase by a factor of 2

Be halved

Remain the same

The cross-sectional area A = πr². If r becomes r/2, the new area becomes A/4. To keep Av constant, v must increase by a factor of 4.

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8) A force of 10 N stretches a spring by 0.05 m. What is the spring constant (k)?

50 N/m

0.5 N/m

2 N/m

200 N/m

According to Hooke's Law, F = kx. Therefore, k = F/x = 10 N / 0.05 m = 200 N/m.

9 / 20

9) A streamline is a line or curve that is everywhere _______ to the velocity vector of the fluid flow.

Equal

Parallel

Perpendicular

Tangent

This is the definition of a streamline; it shows the instantaneous direction of flow at every point.

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10) Two raindrops are falling at their respective terminal velocities. Raindrop A has a larger radius than raindrop B. Which statement is true?

Neither reaches a terminal velocity.

Raindrop B has a higher terminal velocity.

Both have the same terminal velocity.

Raindrop A has a higher terminal velocity.

Terminal velocity is proportional to the square of the radius. A larger radius means a significantly higher terminal velocity.

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11) A solid sphere has a mass 'm' and radius 'r'. Its terminal velocity in a fluid is 'v'. If a sphere of the same material has a mass of '8m', what is its radius?

Mass is proportional to volume, and volume is proportional to r³. If mass increases by a factor of 8, the radius must have increased by a factor of ³√8 = 2.

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12) The drag force on an object moving through a fluid depends on all of the following EXCEPT:

The fluid's viscosity and density

The object's mass

The object's speed

The object's shape and size

Drag is a surface force caused by interaction with the fluid; it does not depend directly on the mass of the object.

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13) A wire of length L and radius r is stretched by a force F, causing an extension ΔL. If a wire of the same material has length 2L and radius 2r, what force is needed to cause the same extension ΔL?

F/2

From Y = (FL)/(AΔL), we get F = (YAΔL)/L. The new area is A' = π(2r)² = 4A. The new length is L' = 2L. So, F' = (Y(4A)ΔL)/(2L) = 2 * (YAΔL)/L = 2F.

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14) Which of these devices does NOT rely on Bernoulli's principle?

Hydraulic Brakes

Paint Sprayer

Venturi Meter

Airplane Lift

Hydraulic brakes operate on Pascal's law, which relates to pressure in a confined, static fluid.

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15) Real fluids differ from ideal fluids because real fluids have:

Potential and kinetic energy

Viscosity and are compressible

Mass and density

The ability to flow

All real fluids possess some viscosity (internal friction) and are compressible to some extent, unlike ideal fluids.

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16) What is the primary reason race cars have inverted wing-shaped spoilers?

To protect the driver in case of a rollover.

To create a downward force to increase traction.

To reduce the overall weight of the car.

To make the car more streamlined and reduce drag.

The inverted wing shape creates higher pressure on top and lower pressure underneath, pushing the car onto the track.

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17) The steady, non-viscous, and incompressible flow of a fluid is a description of:

Real fluid flow

Turbulent flow

Superfluid flow

Ideal fluid flow

These are the three main assumptions made to define an ideal fluid, which simplifies the analysis of fluid dynamics.

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18) The study of fluids in motion is called:

Fluid Dynamics

Solid-state Physics

Fluid Statics

Thermodynamics

This is the correct term for the branch of physics concerned with fluids in motion.

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19) The constant 'A' in the general form of Stokes' Law (F = Aηrv) was experimentally determined to be:

6π

4/3 π

4π

For a sphere moving under laminar conditions, the constant of proportionality is 6π.

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20) A cylindrical pipe has a fluid flowing through it. If the pipe narrows, what happens to the streamlines?

They move farther apart.

They become more crowded together.

They stop.

They remain equally spaced.

In the narrower section, the fluid must speed up. Denser streamlines are used to visually represent regions of higher velocity.

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Fluid Dynamics Test. 5

1 / 16

1) The unit 'poise' is used to measure:

Pressure

Density

Viscosity

Strain

The poise (and the more common centipoise) is a CGS unit of dynamic viscosity.

2 / 16

2) Which term describes a fluid flow that is irregular, unsteady, and changes abruptly?

Turbulent

Laminar

Incompressible

Streamline

This is the correct term for chaotic, unpredictable fluid motion.

3 / 16

3) For a falling spherical object, the net force is given by Fₙₑₜ = Weight - Drag Force. What is the net force when the object reaches terminal velocity?

Zero

Greater than the weight

Equal to the drag force

Equal to the weight

At terminal velocity, the drag force has grown to be equal in magnitude to the weight, so the two forces balance and the net force is zero.

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4) In the term (1/2)ρv² from Bernoulli's equation, ρ is the density of the fluid. What does the entire term represent?

Momentum per unit volume

Dynamic force

Kinetic energy per unit volume

Kinetic energy

Since kinetic energy is (1/2)mv² and density ρ = m/V, then (1/2)ρv² equals KE/V.

5 / 16

5) When water falls from a tap, the stream narrows as it descends. This is a visual demonstration of:

Surface Tension

The Equation of Continuity

Viscosity

Bernoulli's Principle

As the water accelerates due to gravity (v increases), its cross-sectional area (A) must decrease to keep the flow rate (Av) constant.

6 / 16

6) A solid material's ability to be hammered or pressed into shape without breaking is called:

Brittleness

Hardness

Ductility

Malleability

This is the correct term for the ability of a substance, especially a metal, to be deformed or molded into a different shape.

7 / 16

7) Which of these devices does NOT rely on creating a low-pressure zone through high-speed fluid flow?

Engine Carburetor

Barometer

Atomizer

Filter Pump

A barometer is a static device that measures existing atmospheric pressure; it does not involve fluid flow to operate.

8 / 16

8) The pressure at a certain depth in a static fluid depends on the depth, the acceleration due to gravity, and the fluid's:

Density

Volume

Shape of the container

Viscosity

The formula for hydrostatic pressure is P = ρgh, where ρ is the fluid density.

9 / 16

9) The expression for strain energy, Eₚ = (1/2)kx², is mathematically identical to what other physical quantity?

The work done in stretching the spring.

The kinetic energy of the spring.

The gravitational potential energy of the spring.

The power applied to the spring.

The work done against the elastic restoring force is stored as potential energy.

10 / 16

10) The 'swing' of a cricket ball or the 'curve' of a baseball is largely due to:

The Magnus effect, an application of Bernoulli's principle

The Earth's rotation (Coriolis effect)

The conservation of momentum

The ball's weight

The combination of the ball's spin and its travel through the air creates a pressure differential that pushes it to one side.

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11) The term for the constant, maximum velocity attained by an object falling through a resistive medium is:

Instantaneous velocity

Critical velocity

Terminal velocity

Escape velocity

This is the correct term for when the force of gravity is balanced by the drag force, resulting in zero acceleration and constant velocity.

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12) A material has a Young's Modulus of 200 × 10⁹ Pa and is subjected to a stress of 4 × 10⁸ Pa. What is the strain in the material?

0.002

500

8 x 10¹⁹

0.5

Strain = Stress / Young's Modulus. The calculation is (4 × 10⁸) / (200 × 10⁹) = 0.002.

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13) A chimney works best on a windy day because the wind blowing across the top opening:

Increases the pressure at the top, pushing the smoke down.

Cools the smoke, making it denser and harder to draw up.

Blocks the opening, trapping the smoke inside.

Reduces the pressure at the top, helping to draw the smoke up.

The fast-moving wind creates a low-pressure zone according to Bernoulli's principle, which enhances the draft.

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14) An object will float if its average density is _______ the density of the fluid it is in.

Independent of

Greater than

Less than

Equal to

For an object to float, it must be less dense on average than the fluid it is in.

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15) The equation vₜ = (2ρgr²)/(9η) shows that terminal velocity is inversely proportional to which quantity?

The viscosity of the fluid (η)

The acceleration due to gravity (g)

The square of the radius (r²)

The density of the object (ρ)

Viscosity (η) is in the denominator of the equation, meaning that as the fluid's viscosity increases, the terminal velocity decreases.

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16) The structure of polymeric solids like plastics is best described as:

Perfectly ordered and crystalline

Completely disordered and amorphous

A liquid with very high viscosity

Intermediate between ordered and disordered

Polymers consist of long chains that can have both ordered (crystalline) and disordered (amorphous) regions.

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