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The Magnus effect was discovered when an explanation for the low precision of guns was needed. It affects the cylindrical, pointed grenades just as much as any ball. It does not matter how long the rotating body is: Once it rotates, it will create a low pressure area on one side orthogonal to the crosswind direction and a corresponding high pressure area ...


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I believe that when an oblong ball tumbles with backspin its range is increased due to the magnus effect. Most studies of oblong balls analyze spinning rotation about the long axis, but there is some evidence that tumbling about the short axis may enhance the Magnus effect: "The Magnus effect is also exploited in a number of Nature’s designs. Many seed ...


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Use a blunt trailing edge in XFoil, and for the real thing round it any way you want. If you increase local curvature close to the trailing edge, your local flow will simply separate. Then it is irrelevant for the flow whether the trailing edge is rounded or blocky - the separated air will fill up the void and for the outer flow the exact shape of the ...


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I would say that the speed of the gas escaping to vacuum corresponds to the gas temperature. What happens is that you only remove one wall (of a box) and the gas molecules that would bounce off the (removed) wall they just start to freely escape. With the velocity given by $kT$. The opposite wall however still feels the gas pressure. From this, it seems ...


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Lift costs drag Creating lift costs drag. Creating more lift causes more drag. This drag is called induced drag and is the consequence of the wing bending the airflow downwards. To simplify things, let's assume the wing is just acting on the air with the density $\rho$ flowing with the speed $v$ through a circle with a diameter equal to the span $b$ of the ...


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I recently came across this information which seems quite relevant here: When you are comparing equal disk area, then yes staggering them is better than coaxial (in the same column) by roughly 20-30%. But consider the configuration shown below. For a given fram size, when you stagger them you have less room around the circumference of the vehicle's frame ...


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Building on Carl's comment: The way any heavier than air aircraft works is that the wings exert a downward force on the air - increasing the downward momentum of the air results in a net lift force in the wing. Now if you are heavier, you need to either move more air down per unit time, or move it down faster, in order for you to generate sufficient force. ...


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Check out this explanation. Basically, when a wing is flying, it feels a force vector which is not vertical. It points up and back. We call the upward component lift, and the backward component drag. Suppose a plane is loaded to twice its normal weight. Then it needs twice its normal lift to support that weight. It pays a price for this in twice the ...


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It seems like you are incorrectly thinking that the lift force opposes the drag force. There are essentially four forces on an airplane. There is a lift force from the wings - this force points upwards. There is a force of Gravity, which points downwards. There is a force of thrust from the engines pointing forwards, and a force of drag pointing ...


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The acceleration needs to be provided here to conclude the net force on the pilot. Zero g: it shows free fall. Let me elaborate simply : Weight= Mass × g force Now in your case if the pilot goes to 400m/s in 10 seconds from a standstill, he will experience( i deem he'll feel it more than he experiences it :)) his weight FOUR the times as against whilst he ...


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There are lots of papers reporting measurements of the drag coefficient of a sphere below and above supersonic speeds. Glancing through them, it appears the drag coefficient does increase as the speed goes supersonic, but by relatively modest amounts. Obviously a pilot isn't a sphere, and the airflow will be affected by the presence of the plane, so I think ...


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Yes, the force points along the vector of the relative velocity between the object and the air. Quadratic drag is an interesting phenomenon. You have to calculate the net velocity vector (which includes a horizontal and vertical component) and compute the force along that axis; when you then decompose it into horizontal and vertical components you will find ...


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Altitude can indeed have such an effect. As your linked article explains, one can get a rough sense of the aerodynamic force on a spherical ball by neglecting viscosity (i.e., model air as a bunch of ballistic particles that do not drag on one another), in which case the formula is1 $$ F = \frac{16\pi^2}{3} C_l \rho \omega v r^3. $$ The important point is ...


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I believe that yes, it could. However you must also take into consideration that air density may not be the only apprehension that a player is dealing with throughout a game. As to answer your other question multiple world stadiums are covered at a sea level however the highest was located at Estadio Da Baixada, Curitiba which was 920m (3,018 ft). Depending ...


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The aileron will point in the direction that would cause the most drag, it will also flutter a bit. And if by increased alpha you mean the aircraft is flying with high alpha like a jet going super slowly forward at a constant altitude with the nose pointing way up into the air at a high angle, then technically the ailerons would go up in relation to their ...


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Wings provide lift because they direct air downwards. They direct air downwards in two ways. In part, the bottom of the wing slopes downward a bit and just pushes the air down as it moves forward through the air. But this is a small effect. The top of the wing is more important. The top of the wing pulls the air down partially by providing a ramp. The rear ...


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Essentially a fixed-wing aircraft flies because it moves through the air and has a fixed wing which is angled to the direction of airflow. A component of the drag force acting on the wing acts in the direction (up) opposite to the direction (down) of the aircraft's weight force. An aeroplane wing acts like a weather vane responding to the relative flow of ...


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That's the venturi effect. There's a nice Khan Academy video here.


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One-dimensional shocks are modeled using the Rankine-Hugoniot relations. These give the jump in density, pressure, and temperature across an infinitely thin shock and are found by conducting a control-volume analysis of the region around the shock (conservation of mass, energy and momentum). The relations are: $$\frac{p_2}{p_1} = 1 + \frac{2 ...


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Flutter is only possible if you have similar structural and aerodynamic frequencies. One without the other would produce much lower amplitudes. Look at a mass-spring system suspended on an eccentric tappet which sits on the edge of a small rotating wheel. When the wheel turns, it raises and lowers the top of the spring, and the mass on the bottom will ...



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