please friends,in other to maintain a constant radius(steady turn),which force balances the centripetal force.........I am getting confused,I said it's 'weight' but my classmate said it is 'lift'
Yes. You fly the airplane so that no sideways force is felt in the turn. A blindfolded passenger wouldn't know that the airplane is in turning flight, except that they might notice a slight increase in gravity pushing downward in their seat....
And would a good turn mean equal pressure on the cheeks?
There are four forces affecting an aircraft: thrust, lift, drag, and weight.
One of these provides the centripetal (center-seeking) force to accelerate the plane perpendicular to the direction of the velocity vector, and parallel to the ground. Which one could it be?
I just read an explanation somewhere (don't remember) that the centrifugal force exists as a 'real' force from the point of view of an accelerating reference frame (i.e. the frame rotates with the aircraft, so the forces are "balanced" with no net force on the craft). In an inertial reference frame (of which we are more accustomed to in real life), the presence of a centrifugal force that counters the centripetal force would quite obviously prevent the plane from changing direction, i.e. the forces must be unbalanced in order to effect a change in the velocity vector.I don't know if they have ever corrected it, but the official FAA diagram of the forces acting on an aircraft in a turn was (is?) wrong for decades as it showed, properly, the horizontal and vertical components of lift and then the weight (thrust and drag were into/out-of the page and so weren't depicted). But then they just HAD to show the "centrifugal" force acting outward with the next result being that their diagram showed zero net force acting on the aircraft.
But if the view is from the accelerating reference frame of the airplane, then the plane ISN'T turning and the whole question is nonsensical. You can't ask about the forces that are causing a plane to turn unless you are talking about forces within a reference frame in which the plane is, in fact, turning.I just read an explanation somewhere (don't remember) that the centrifugal force exists as a 'real' force from the point of view of an accelerating reference frame (i.e. the frame rotates with the aircraft, so the forces are "balanced" with no net force on the craft). In an inertial reference frame (of which we are more accustomed to in real life), the presence of a centrifugal force that counters the centripetal force would quite obviously prevent the plane from changing direction, i.e. the forces must be unbalanced in order to effect a change in the velocity vector.
Another way to look at this: an object who's thrust exceeds its weight accelerates uniformly along it's direction vector. The imbalance causes the acceleration. If viewed from within an accelerating reference frame (coinciding with the instant velocity of the object), the thrust is balanced by the inertial mass of the object, thus the net forces become equal.
But I think we had this conversation already, a few weeks ago.
Edit: BTW, I wonder if the OP ever formulated the correct answer...
Please see my edit.But if the view is from the accelerating reference frame of the airplane, then the plane ISN'T turning and the whole question is nonsensical. You can't ask about the forces that are causing a plane to turn unless you are talking about forces within a reference frame in which the plane is, in fact, turning.
As far as thrust exceeding the weight -- I'm not sure what you are talking about -- nor what direction vector you are talking about. The thrust of the vast majority of airplanes do NOT exceed their weight, yet they accelerate just fine as long as the thrust exceeds the drag.
It is the centripetal force that is keeping the plane in the turn. If you balance it, then the plane will no longer be in a turn.i still haven't got an answer.....which among these forces:thrust,weight,lift and thrust?....
What other options were you given? I don't think either of those is correct.please friends,in other to maintain a constant radius(steady turn),which force balances the centripetal force.........I am getting confused,I said it's 'weight' but my classmate said it is 'lift'
And it sounds more like guessing than thinking.What other options were you given? I don't think either of those is correct.
No.I would guess that lift is the expression of centripetal force and mass(inertia of craft) is the counter force.
Is that close?
by Aaron Carman
by Aaron Carman
by Jake Hertz