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This is just curiosity btw, so if it is too hard to find out, then don't worry about it

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In summary: You could probably reach about 500 m/s in around 20 seconds, which is about 1100 mph.[/QUOTE] In summary, if a passenger plane with a mass of 72574.7792 kg and traveling at a speed of 500 knots lost control and went down at a 40 degree angle, it would take approximately 20 seconds to reach a speed of 500 m/s before hitting the ground, assuming a drag coefficient of 0.012 and a frontal area of 10 m^2. However, the terminal velocity of the plane would be around 2800 m/s, which may not be reached in the short amount of time before impact.

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This is just curiosity btw, so if it is too hard to find out, then don't worry about it

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Welcome to the PF.ThePizzaDeliveryGuy said:

This is just curiosity btw, so if it is too hard to find out, then don't worry about it

Have you had trigonometry yet in school? That's the easiest way to figure out this problem.

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No i have not had it yetberkeman said:Welcome to the PF.

Have you had trigonometry yet in school? That's the easiest way to figure out this problem.

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berkeman said:Welcome to the PF.

Have you had trigonometry yet in school? That's the easiest way to figure out this problem.

Only if you neglect air resistance. Given that the title included the phrase "terminal velocity", that would imply that the question is not intended to neglect air resistance. In that case, this is not a simple problem to solve. You'd have to simply estimate to some arbitrary (and likely poor) level of accuracy.

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That is quoting the mass to the precision of 1/10 of a gram. You would have been better off to say 160,000 pounds.ThePizzaDeliveryGuy said:has a mass of 72574.7792 kg

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True, but I assumed that the speed would not be much more than 500 knots. Maybe that was too much of a simplification on my part.boneh3ad said:In that case, this is not a simple problem to solve.

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ThePizzaDeliveryGuy said:This is just curiosity btw, so if it is too hard to find out, then don't worry about it

Then download X-Plane and try it out. Much more fun than trying to calculate something like this.

http://www.x-plane.com/desktop/home/

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berkeman said:True, but I assumed that the speed would not be much more than 500 knots. Maybe that was too much of a simplification on my part.

Regardless of speed, air resistance complicated matters substantially. If there was no resistance then it is sime kinematic a. If it was a sphere with air resistance, that's relatively easy to estimate. But with a plane, it will depend so much on what orientation the plane has as it is falling that it's an intractable problem.

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ThePizzaDeliveryGuy said:A passenger plane is traveling at a speed of 500 knots, has a mass of 72574.7792 kg

Looks like an insect sneaked on board that day and pushed the weight up an extra 0.2g. :-)

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Here is a table of some typical drag coefficients. http://www.engineeringtoolbox.com/drag-coefficient-d_627.html

If we take the plane to have a drag coefficient of ##c_d = 0.012##, and a frontal area of ##A = 10 m^2##, and density of air ##\rho = 1.2 kg/m^3##,

##F_d = c_d \rho v^2 A##

Terminal velocity ##v_f## is reached when the vertical component of the drag equals the force of gravity.

##mg = F_d \sin 40^o##

therefore

##v_f = \sqrt{ \frac{mg}{c_d \rho A \sin 40^o}}##

~ 2800 m/s

Is it really that high? Maybe the drag is higher than 0.012.

Anyways, you probably wouldn't have enough time to reach terminal velocity.

Terminal velocity is the maximum speed that an object can reach when falling through the air. It is dependent on the object's mass, surface area, and the density of the air. When an object is falling, it will continue to accelerate until it reaches a point where the force of air resistance is equal to the force of gravity, causing it to reach a constant speed. Adding speed to an object will not affect its terminal velocity, as it will still reach the same maximum speed due to the balance of forces.

The average terminal velocity of a passenger plane is approximately 150-180 miles per hour. This can vary depending on the type of plane, its weight, and the weather conditions.

Air density plays a significant role in determining the terminal velocity of a passenger plane. In denser air, there is more resistance, causing the object to reach its terminal velocity at a lower speed. In less dense air, there is less resistance, and the object will reach its terminal velocity at a higher speed.

The two main factors that can increase the terminal velocity of a passenger plane are weight and surface area. A heavier plane will fall faster than a lighter one, and a larger surface area will experience more air resistance, causing it to reach its terminal velocity at a lower speed.

No, the terminal velocity of a passenger plane is not the same during takeoff and landing. During takeoff, the plane is accelerating and has not yet reached its maximum speed. During landing, the plane is decelerating and will not reach its terminal velocity as it is being controlled by the pilot. The plane's terminal velocity is only reached when it is in freefall, such as during a steep descent or in an emergency situation.

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