Can You Simplify Calculating Drag Coefficient for an Inverted Cone?

In summary, the speaker has a task to calculate the air drag coefficient experimentally, and has used a cone dropped from a height of 1.5 m to measure time and derive equations for velocity and acceleration. They are now looking for a simpler method and suggest dropping the cone from a higher height to reach terminal velocity, then measuring size, weight, and velocity to calculate the drag coefficient directly. They also mention using a video camera with a ruler in the background to measure velocity. The cone is made of hollow paper, tip down, and weighs 80g/m^2. The speaker also asks if it is possible to calculate terminal velocity for an inverted cone.
  • #1
fizzyfiz
36
1
Thread moved from the technical forums, so no Homework Template is shown.
Summary: Hello, I have a task to calculate the air drag coeficient experimentally. I have a cone which I had dropped from height of 1.5 m and measured the time. Then I derived the equation of of velocity and acceleration but they are very complicated. Is there any simpler method?

a=g-k/m*V^2
 
Physics news on Phys.org
  • #2
Is the cone solid, made of lead ? Please be a little complete ...
 
  • #3
A cone made from a rolled up and taped piece of paper could reach its terminal velocity in 1.5 m, so you should be able to get a good measurement of drag coefficient. On the other hand, a cone made of wood or metal would be almost unaffected by air drag in that distance, so it would be almost impossible to measure drag coefficient.

A simple method would be to drop the cone from a height high enough that it reaches terminal velocity. Then measure the size, weight, and velocity, and calculate the drag coefficient directly from the drag equation. Velocity can be measured using a video camera with a ruler in the background.
 
  • #4
Ok so I should mark heights and I will know that cone reached its terminal velocity if the same distance will be traveled in equal times?
 
  • #5
Hollow paper it is. Tape light enough ? Ratio height/diameter ? Tip up or down ? Stabilized ?
As
BvU said:
Please be a little complete ...

fizzyfiz said:
reached its terminal velocity if the same distance will be traveled in equal times?

Yep. Maybe use a video.
 
  • #6
It is a cone made of paper, tip down, 80g/m^2 . I caculated mass
 
  • #7
BvU said:
Hollow paper it is. Tape light enough ? Ratio height/diameter ? Tip up or down ? Stabilized ?
Hollow paper
1571903904825.png
, tip down
1571903907108.png
. One by one they come out. I keep on dragging for the others ...

Can you calculate a terminal velocity for an inverted cone ?
 

Related to Can You Simplify Calculating Drag Coefficient for an Inverted Cone?

1. What is the purpose of a drag coefficient experiment?

The purpose of a drag coefficient experiment is to measure the amount of air resistance (drag) that an object experiences as it moves through a fluid. This information is important for engineers and scientists to understand the aerodynamics of different objects and to design more efficient vehicles.

2. How is the drag coefficient calculated in an experiment?

The drag coefficient is calculated by dividing the drag force on an object by the product of the fluid density, the object's velocity squared, and its frontal area. This can be done by measuring the object's motion in a controlled environment, such as a wind tunnel, and using mathematical formulas to determine the drag coefficient.

3. What factors can affect the drag coefficient in an experiment?

The drag coefficient can be affected by various factors such as the shape and size of the object, the speed at which it is moving, the density and viscosity of the fluid, and the roughness of the object's surface. Other factors such as the angle of attack and the presence of turbulence can also influence the drag coefficient.

4. How do scientists use drag coefficient data in their research?

Scientists use drag coefficient data to analyze the aerodynamics of different objects and to better understand the forces that act on them as they move through a fluid. This information is also important in developing and improving technologies such as aircraft, cars, and sports equipment.

5. What are some common methods for measuring drag coefficient in an experiment?

Some common methods for measuring drag coefficient in an experiment include wind tunnel testing, water flume testing, and computer simulations. These methods allow scientists to control the variables and accurately measure the drag coefficient for different objects and conditions.

Similar threads

  • Introductory Physics Homework Help
Replies
6
Views
2K
Replies
5
Views
955
  • Introductory Physics Homework Help
Replies
7
Views
2K
Replies
3
Views
4K
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
11K
Replies
1
Views
1K
  • Introductory Physics Homework Help
2
Replies
36
Views
4K
Replies
6
Views
733
  • Introductory Physics Homework Help
Replies
5
Views
2K
Back
Top