Questions tagged [drag]
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Performance catamaran
I was looking at You Tube build videos of small performance catamarans
Most of the builders chose both the sides of the catamaran to have a triangular profile shape like this one here:
On the other ...
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How does an airflow sensor work?
There are 4 piezoresistive sensors placed at position A, B, C and D.1
I searched for the working principle of an airflow sensor and I saw this. If I am trying to identify the expected displacement ...
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Why do wing-tip vortices cause an induced angle of attack upstream?
My question is the following. Wing-tip vortices induce a downward flow on the root side of the wing. So, if this induction happens at the wing, and these vortices are then shed downstream, why is ...
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Wooden Sailing Ships - Why The Drag Pieces of Common Logs Were Shaped like Sections of a Circle?
I was reading the website What is the difference between a nautical mile and a knot?, and it said
The common log was a rope with knots at regular intervals, attached to a piece of wood shaped like a ...
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Drag force and coefficient for cylinder through water
Pushing a cylinder through the water with an angular velocity of $\omega$.
The cylinder diameter and length are $D$ and $L$ respectively and the length from the rotation point to the center of the ...
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Is there a way to simulate the drag effect created by acceleration while in a stationary object?
There was a video of a train that had tvs in the windows so it appeared the rider was moving across the landscape. If the train was stationary the passenger would not believe the ride was real because ...
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Drag coefficient of a complex object made using simple objects (with known drag coefficient) in small Re?
Let say you have an object made of simple objects (figA1). You know the drag coefficients of simpler objects (here spheres and rods, figB1). Is there a way to estimating the drag coefficients of the ...
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Is the drag coefficient/velocity of of a vehicle based on frontal area?
Does the frontal area of a vehicle determine the velocity/drag coefficient of a car?
A Ferrari 458 has a Cd of 0.33 while a Corvette C6 has a Cd of 0.29. Does this mean the Corvette will have less ...
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Calculate effect of drag on ball in motion
So I’ve been trying to work out the range of a ball that has been projected by two spinning discs please when accounting for drag-
This is what I got so far:
$V=V\cos\theta$, $T=2V\sin\theta/g$ , and $...
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Does more downforce affect the acceleration and top speed?
How can downforce make a race car faster, apart from being faster around corners? I just recently learned that downforce can help a car accelerate from 0-60 mph faster. Usually, I thought drag didn't ...
user34865
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How long does it take and how far does it travel a sphere in free fall before reaching a percentage of the terminal velocity?
Assume a sphere (hail) that is free dropping in air. At some the sphere will reach close to the terminal velocity. The question is:
how long $t_p$ in seconds does it take before a percentage $p$ of ...
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Does the terminal velocity of a sphere in free drop increase with increasing diameter?
I was trying today to calculate the terminal velocity of a hailstones with increasing diameter and mass. I was trying to figure out if larger hailstones will have a higher impact velocity or lower.
I ...
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Does the aerodynamic force qualify as a viscous damping force in the Mechanical Harmonic Oscillator
When reading about a harmonic oscillator, the most common form of damping is proportional to the velocity.
$$F_D = c \;\dot{x}$$
Without giving much thought to viscous damping, one example I always ...
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Required power to spin fan at certain RPM
I have a flat piece of wood shaped like this:
And it is turning around axle.
What i would like to know is, if it is rotated e.g. at 1000 RPM, how much power would that take?
I know that drag force ...
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How do you determine the L/D ratio of F-117 Nighthawk?
I was trying to look for an L/D ratio published everywhere on the web and I can't seem to find it (for a project). Since I couldn't find it, I wanted to try calculating myself. Can't seem to find $C_l$...
