The increase in terminal velocity is not marginal, it increases at double the rate as mass.
Whoops, no it doesn't. It's the square root of double the difference. Still not marginal.
Science!! Fucking magnets, how do they work?
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Whoops, no it doesn't. It's the square root of double the difference. Still not marginal.
Tuco
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Your arguments are unfounded and your mathematical fortitude is inexact!
pussy!
Serious answer: your equation depends on torque being applied to the wheels from the engine (or brakes, I guess) which doesn't happen in an airplane.
Ok since you guys refuse to stop engaging him, let's try it a different way.
Let's say you have a plane that is on a infinite treadmill already heading backwards at a very high speed. What happens when you turn the engine on? Does the speed that it is traveling backwards diminish?
Let's say you have a plane that is on a infinite treadmill already heading backwards at a very high speed. What happens when you turn the engine on? Does the speed that it is traveling backwards diminish?
Serious response: no it doesn't. Every wheel, no matter how it is propelled forward, has rolling resistance in the opposite direction. Rolling resistance is the product of non-elastic effects of wheel deformation.
Tuco
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BRO THAT QUESTION WASN'T FOR YOU
Oh well, he got an even simpler question wrong, so it's hopeless.
Does it hurt that you can't understand the problem setup that I sent you?
I solved for the required coefficient to counteract the thrust, then solved for the velocity required to get that c. The coefficient at 470mph on asphalt compares to the coefficient at practical speeds in sand.
Understand now? Or shall we continue this herpin derpin goat rope?
I solved for the required coefficient to counteract the thrust, then solved for the velocity required to get that c. The coefficient at 470mph on asphalt compares to the coefficient at practical speeds in sand.
Understand now? Or shall we continue this herpin derpin goat rope?
Well you didn't show it here.
From this page:http://wiki.answers.com/Q/How_much_t...y_a_Boeing_747
224,000 lbs of thrust.
Where did you come up with a number that large for rolling resistance based on the formula you linkedhttp://www.engineeringtoolbox.com/ro...ce-d_1303.html.
A 747 has maximum takeoff weight of 875,000 lbs. Use that number.
From this page:http://wiki.answers.com/Q/How_much_t...y_a_Boeing_747
224,000 lbs of thrust.
Where did you come up with a number that large for rolling resistance based on the formula you linkedhttp://www.engineeringtoolbox.com/ro...ce-d_1303.html.
A 747 has maximum takeoff weight of 875,000 lbs. Use that number.
Based on the problem setup and numbers I sent Tuco. If it is moving backwards and the wheel speed is greater than 470mph it slows down, but keeps moving backwards. If the wheel speed is less than that it will eventually reverse direction, pick up forward speed, and take off.
It's simple force balancing, you just can't neglect parasitic forces unless you're arguing ideal conditions.
It's different for every plane, as the weights and thrusts are different. The weight and thrust I used are in the post Tuco shared.
If it's moving backwards at the speed of the treadmill the wheel speed is 0 so you are wrong even there.
Your tire pressure is wrong, you have to convert it to bar, not psi.
And you first have to solve for c using the F=cW formula. Where F is thrust, and W is weight.
You're stuck on thinking c doesn't change, and that formula shows that it does. It is a function of tire pressure and velocity.
And you first have to solve for c using the F=cW formula. Where F is thrust, and W is weight.
You're stuck on thinking c doesn't change, and that formula shows that it does. It is a function of tire pressure and velocity.
Did you remember to account for the reduction in friction owing to the lift provided by the wings of the plane? No, of course you didn't.
Tuco
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