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Questions tagged [drag]

The force on a body resulting from it's motion through a fluid (gas or liquid). This force is directly opposed to the direction of travel.

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Understanding the math behind a falling object attached to a parachute

I'm trying to understand the mathematics behind calculating the total speed and force of a $40 kg_f$ object hooked up to a parachute, falling to Earth. From what I understand, the formula for this is ...
1k views

Finding the diameter a parachute must be to land a probe on Mars at specific speed

Hi I'm trying to solve this textbook example but I don't know where to begin; NASA has decided to send an experimental probe to Mars. Its weight on earth is $40 kg_f$. When the probe is near the ...
4k views

Kinetic Energy of Stone

If a stone is launched upward, of which is subject to gravity and air resistance, which of the following will have a greater kinetic energy? The stone at a point on its way up, or the stone at the ...
485 views

Parabolic motion and air drag

Are this equations correct, in order to calculate the parabolic motion of an arrow with the computation of the drag with the air?  \begin{cases} x(t)=\left(v_0-\frac{1/2C_DA\rho v_0^2}{m}t\right)\...
8k views

Friction due to air drag at high speeds

I am trying to set up this problem, but I am not sure how to go about doing so. (From University Physics, Young & Freedman): You throw a baseball straight up. The drag force is proportional to ...
342 views

How does Baumgartner slow his velocity so that the parachute can open up?

How does Baumgartner slow his velocity so that the parachute can open up? What is Baumgartner's speed just before his parachute opens? What causes his speed to slow down just before the chute opens? ...
68k views

Could someone jump from the international space station and live?

Felix Baumgartner just completed his breathtaking free-fall skydiving jump from $120,000\,\text{feet} = 39\,\text{km}$ above the Earth, breaking the speed of sound during the process. I was wondering ...
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How Felix Baumgartner has reached the speed of sound quickly

I have watched Felix Baumgartner freefall; but I wonder how Felix has reached the speed of sound quickly, in a matter of some seconds, then we had no idea of its speed? Any explanation please.
1k views

Time of a ball going up and down with air resistance

A ball is shot directly upward, and then it comes back to the place where it was shot. Suppose we have air resistance. Suppose $t_1$ is the time period from the moment that the ball was shot to the ...
499 views

Does air resistance ever slow a particle down to zero velocity?

If a particle moves in a place with air resistance (but no other forces), will it ever reach a zero velocity in finite time? The air resistance is proportional to some power of velocity - $v^\alpha$, ...
13k views

Why would a fat skydiver fall first in free fall?

I was having one of those obnoxious conversations with a friend where he was arguing that a fat skydiver would reach the ground faster than a skinny skydiver. To me it seemed as obvious that the world ...
494 views

How can the Air friction force be applied to an object?

Suppose we have an object and we throw it straight upward in the air. How do we apply the Air friction force to this object while moving upwards and after that downwards? Sorry if it's easy because I'...
8k views

Is it possible to find out the distance traveled by a car if the force applied on it is given?

Say you have car which produces $F$ amount of force which is transferred to the wheels directly. Now assuming that there is air friction which is causing a retarding force proportional to the ...
402 views

How closely may an artificial satellite orbit Earth without decaying appreciably each orbit?

Just what the title states. An artificial satellite will orbit Earth with some defined angular momentum. An aircraft,on the other hand, relies upon it's engines to provide continuous forward velocity &...
17k views

Equations for an object moving linearly but with air resistance taken into account?

I know (from Kinematics) that for an object moving linearly with an acceleration and without air resistance the following equations can be used to determine v(velocity) or x(position of the object) at ...
723 views

Bicycle Wheel Drag in Slipstream

I was recently driving behind a car that had a bicycle mounted on a carrier over the rear bumper. The bicycle wheels were not bound so they were rotating in the slip-stream of the car. I wonder, the ...
2k views

What would be an appropiate shape for a parachute?

I'm trying to design a parachute that minimizes the descent velocity, but I'm not sure what shape I should use. From what I've read, ellipse-shaped parachutes are too aerodynamic and minimize drag, ...
3k views

Free fall of two spheres made of same materials, different masses, with air resistance

Two people falling with the same parachute will gain different speeds if their masses are different. The upward air drag will needed to be bigger for a heavier person, since gravitational force is ...
881 views

What is the typical orbital life of an artificial satellite?

The orbit of satellites around Earth eventually decays, or so I read. This is typically caused either by atmospheric drag, or by tides. I would assume most satellites have a limited service life in ...
1k views

At what g is terminal velocity not terminal?

How weak would gravity need to be in order for a human to reliably survive the terminal velocity of falling through air? (Context: watching scifi on a space station with a variety of artificial ...
7k views

Would a fast inter-stellar spaceship benefit from an aerodynamic shape?

Some (generous) assumptions: We have a spaceship that can reach a reasonable fraction of light speed. The ship is able to withstand the high energies of matter impacting at that speed. Given the ...
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I'm trying to build a ballistics simulation where I shoot a cannonball. I want to allow for drag and am trying to work out the math to do so. I can work the drag out using $F = C_d\times S\times V^2\... 3answers 12k views What are the precise statements by Shouryya Ray of particle dynamics problems posed by Newton which this news article claims have been solved? This recent news article (here is the original, in German) says that Shouryya Ray, who moved to Germany from India with his family at the age of 12, has baffled scientists and mathematicians by ... 3answers 6k views Does wind speed things up or accelerate things? This question may seem odd, but I can't think of anything better. So I'll go straight to the point. Let's say there's a projectile in air going east, shot at a certain angle, with a certain speed. ... 4answers 18k views Why does a parachute decrease terminal velocity? Terminal Velocity depends on two things: surface area and speed. These are inversely proportionate. If both these variables affect terminal velocity, why do parachutes slow you down? Initially you ... 1answer 1k views Why does a coin falls faster when it's flipping as well? From my experiments with measuring how fast a coin falls, I have consistently measured a faster falling rate for a coin that flips as it falls. As an example, a coin dropping on its edge from height ... 4answers 8k views Does a ski racer with a larger mass have an advantage? Does a ski racer with a greater mass have an advantage over a racer with a lesser mass? If mass of one racer is 54 kg and the mass of a more slender racer is 44 kg I know the speed at which they ... 9answers 2k views Physics Paradox about Newtons Second Law$F=ma$If force equals mass times acceleration, wouldn't a basketball dropped from the top of the Eiffel tower exert the same force on the ground as a basketball dropped a foot off the ground? They both have ... 1answer 4k views How to modify the bullet trajectory based on the ballistic coefficient? I am new to the physics surrounding bullet trajectory and how it is calculated. I am a software developer and I am working on a ballistics calculator for rifles. I am using wiki for the trajectory ... 3answers 322 views How can I modify the bullet trajectory based on the ballistic coefficient? [duplicate] Possible Duplicate: How to modify the bullet trajectory based on the ballistic coefficient? I am new to the physics surrounding bullet trajectory and how it is calculated. I am a software ... 3answers 2k views Why do some satellites fall to Earth? In another question How does Newtonian mechanics explain why orbiting objects do not fall to the object they are orbiting?, one can read an affirmative answer. They how do you explain satellites ... 1answer 770 views Realistic projectile motion I am working on a project involving a simulation of the motion of a projectile (in 3D) aimed at a moving target. The way projectile motion is analyzed in most introductory physics books is not ... 2answers 3k views Is the wind's force on a stationary object proportional to$v^2\$?

I am on a boat docked at Cape Charles, VA, about 30 or 40 miles from the center of Hurricane Irene. This understandably got me thinking about the force of wind on the boat. Since air friction is ...