Just forget its a plane, as its pointless calling it that as due to all the assumptions and restrictions on it, it doesnt behave like one. Its simply an object in 2-d with no drag and air resistance. Makes the questions much simpler and avoids all confusion.
Physics Question
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Newtons second law of motion. The bank of the wings is imparting an unbalanced force in the x-axis. Unbalanced force = Acceleration. Acceleration = Speed increasing.
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Good to see that at least 10% of people on here know what they're talking about! Newton would be turning in his grave. I made this to demonstrate that the answer is path #1.
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Well the original question had this plane with a forces diagram showing only the lift and mavity, showing the plane travelling at a known speed in a circular path of a known diameter, and we had to work out the angle which the plane was banking. I then told my teacher that it wouldn't go in a circular path and then came this question. That is why it is 'oversimplified' (although who is to say how simplified the question should be if the person who posed it can't?) And even with it being this simple, people seem to disagree plenty.
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Devise an experiment to either prove or disprove your theory, from that extrapolate the rule to govern the theory.
Wouldn't this be best described as a boat with two propellers? One at the rear moving the boat forward at a constant speed, and one on the left of the boat, right in the middle [so it doesn't rotate] pushing the boat to the right, with the power constantly being increased?
It makes sense in my head!
It makes sense in my head!
It could be constant speed if you neglected water friction.
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If you dont apply some rudder side slip will mean you eventually hit the ground. So lets ignore that.
As there is no dihedral in the wing geometry (wings angled slightly up) to self correct the bank it will fly around in a circle as the lift has a lateral component applied a sideways force to the aircraft.
As there is no dihedral in the wing geometry (wings angled slightly up) to self correct the bank it will fly around in a circle as the lift has a lateral component applied a sideways force to the aircraft.
The OP says to ignore air resistance, so if the plane has a constant velocity, the only forces applied are mavity and lift then the rudder position would be meaningless (ignoring the air resistance), so the OP seems to be irrepairaby flawed. A plane flying through a vacuum (no resistance) would just travel in a straight line.
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Soldato
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Good point.
Depends if the argument is about what a plane would do and this diagram is an attempt to discuss it OR if its about the FBD of the actual plane as drawn in a theorectical world.
Hard to view it so simple to be honest.
Its hard
Depends if the argument is about what a plane would do and this diagram is an attempt to discuss it OR if its about the FBD of the actual plane as drawn in a theorectical world.
Hard to view it so simple to be honest.
Its hard
There is no air resistance, but the wings generate lift, the force of that lift however acts through the centre of mass of the plane, which means it cannot induce any rotation. So there is an acceleration in one direction, and a constant velocity in another. Basically forget it's a plane at all.
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Surely the plane would just accelerate sideways.
Lift and mavity by your own admission are the only forces.
Vertical component of lift and mavity cancel and the side force provided by the horizontal component of lift (induced by the roll) provide the only non-reacted force.
Lift and mavity by your own admission are the only forces.
Vertical component of lift and mavity cancel and the side force provided by the horizontal component of lift (induced by the roll) provide the only non-reacted force.
Neglecting things is what is getting this thread in a tangle!
"Imagine a plane, that has absolutely nothing in common with an actual plane and ignores 99% of the forces and behaviours that make a plane a plane" does not make for a well structured question.
A boat with two perpendicular propellers makes far more sense
Yeah, hence path 1.
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Neglecting things is what is getting this thread in a tangle!
"Imagine a plane, that has absolutely nothing in common with an actual plane and ignores 99% of the forces and behaviours that make a plane a plane" does not make for a well structured question.
A boat with two perpendicular propellers makes far more sense
argh I am seriously getting fed up with people moaning that I have said to ignore most forces... The question would be perfectly fine if you read which forces are to be included. Is it really THAT hard to consider 2 forces and nothing else, and say what would happen?? Why does it matter that '99%' of the forces are ignored?? If we included every single force, it would be a completely different style question, but how it is, it is perfectly adequate. This is evident as a whole load of people have somehow managed the almost impossible feat of answering without moaning "You've ignored too many forces!!!!!!!!!!!!!!"... Seriously........
Indeed. Although the whole question seems botched up somehow. However, if the curve continues long enough it would result in path 2. What are the respective values for lift v mavity? If the plane has no change in altitude then the force of mavity must be equal to the force created by lift, if all else is ignored, then the plane is travelling in a straight line or indeed motionless.
If you ignore it is a plane and treat it as a particle then I'd go with path 1.
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Woaaaah, nelly! I understood what you meant from the beginning. I was merely commenting on the fact people have spent the majority of this thread considering an actual aeroplane and talking about ailerons and yaw and such, when in reality your scenario is nothing of the sort.
Breathe, woman!
Besides, it's clearly a boat!