Physics of Drag and Terminal Velocity

Define terminal velocity in the context of fluid dynamics.

• Terminal velocity is the constant speed that a freely falling object eventually reaches when the resistance of the medium through which it is falling prevents further acceleration.

• Terminal velocity is the velocity at which an object stops moving in a fluid.

• Terminal velocity is the speed at which an object starts accelerating in a fluid medium.

• Terminal velocity is the maximum speed that an object can reach when falling through a vacuum.

How is Stokes' law applied in the calculation of drag force?

• Viscosity of the fluid is not a factor in the calculation of drag force using Stokes' law.

• The formula for drag force using Stokes' law is Fd = 4πηrv.

• Stokes' law is applied in the calculation of drag force by using the formula Fd = 6πηrv, where Fd is the drag force, η is the viscosity of the fluid, r is the radius of the object, and v is the velocity of the object.

• Stokes' law is used to calculate buoyant force instead of drag force.

What are the factors that affect the drag force experienced by an object?

• Color, weight, temperature, and material

• Shape, size, speed, and fluid density

• Altitude, humidity, time of day, and shape

• Friction, gravity, air pressure, and sound

Calculate the viscous drag force acting on an object with a velocity of 5 m/s and a drag coefficient of 0.2 Ns/m^2.

• 3.0 N

• 2.5 N

• 1.0 N

• 4.0 N

Explain the concept of terminal velocity and its significance in the context of falling objects.

• Terminal velocity is the speed at which an object accelerates infinitely while falling.

• Terminal velocity is only relevant in the context of space travel.

• Terminal velocity is a constant speed that changes depending on the object's shape.

• Terminal velocity is significant because it determines the maximum speed at which an object can fall through a fluid. Understanding terminal velocity is crucial in various fields such as physics, engineering, and skydiving, as it helps predict the behavior of falling objects and ensures safety measures are in place.

In what scenarios does Stokes' law become inaccurate in predicting drag force?

• Low Reynolds numbers

• High Reynolds numbers, turbulent flow, non-spherical particles, complex geometries

• Laminar flow

• Spherical particles

How does the surface area of an object affect the drag force it experiences?

• Surface area affects drag force by increasing it with larger surface areas and decreasing it with smaller surface areas.

• Surface area has no effect on drag force

• Smaller surface areas increase drag force

• Larger surface areas decrease drag force

A sphere with a radius of 0.1 m falls through a fluid with a viscosity of 0.01 Ns/m^2. Calculate the terminal velocity of the sphere.

• 0.15 m/s

• 0.18 m/s

• 0.25 m/s

• 0.22 m/s

Discuss the relationship between the velocity of an object and the drag force acting on it.

• There is no relationship between the velocity of an object and the drag force.

• The drag force decreases with the velocity of the object.

• The relationship between the velocity of an object and the drag force acting on it is that the drag force increases with the velocity of the object.

• The drag force remains constant regardless of the velocity of the object.