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Originally Posted by Wisha Haddan H3
Thank you for the coherent explanation. The only flaw in your evaluation lies in your application of the 3rd law of motion. "For every action there is an equal and opposite reaction".
A car on the conveyor would behave exactly as you describe, since its forward motion is dependent on the force its wheels apply to the conveyor surface. The wheels turn, exerting rearward force on the conveyor belt. The conveyor rolls, absorbing the force and negating forward motion relative to the ground next to the conveyor and the air around it. In other words, although the car moves forward relative to the conveyor, it remains stationary relative to the ground and air.
However, an airplane doesn't have drive wheels. Its forward motion depends the force of the props applied directly to the air. The props turn, exerting force on the air. As air is pushed rearward, the props are pushed in the opposite direction and the plane moves forward through the air, rolling over the conveyor's surface. Meanwhile the conveyor tries to spin, as if to counteract the forward motion of the plane, but the plane's wheels roll freely over it at higher and higher speeds. As the props push air rearward, the wings slice through the static air around the plane until the airflow over the wings produces enough lift for takeoff.
Nothing can stop the plane from taking off unless the tires blow out. Then, the extra friction between the landing gear and the conveyor could crash the plane or slow it down enough to prevent takeoff velocity.
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You simply don't get it. It has nothing to do with it.
The question itself is self-limiting. Regardless of tires, planes, trains or automobiles. The moment it states that the conveyor will match speed with the airplane, period, it is stating that the plane will never move relative to the air. It will never gain speed.
Has nothing to do with physics. It's logic being applied to the question. THAT'S THE REASON FOR THE YES/NO ANSWER.
The question is in itself flawed.
The crap you are reading on some physics site is accurate if you pose the question where the speed is relative to the planes wheels or relative to anything. But since it is left wide open, an assumption would have to be made to suggest that the plane ever moves.
The reason is because due to the limits of the question, it's suggesting that the plane never breaks from zero speed.
It doesn't matter what type of propulsion is used. Whether its magnetic, some big hand, jet, prop, plasmic or whatever. The plane can never move simply because the equation offered by the question says it can't.