777 down.
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Having read most of the conveyor saga and taking the OP back to basic principles, how does the aircraft move forward to create airspeed if the conveyor is cancelling out the ground speed?
One of the "experts" said earlier something about putting an item on the conveyor and pushing it forward against the conveyor direction. This of course can be done but not without increasing the speed of the item in relation to the belt. This of course is not possible with our aircraft because the speeds are matched in the original question.
No airspeed = no take-off with conventional aircraft. What have I missed?
One of the "experts" said earlier something about putting an item on the conveyor and pushing it forward against the conveyor direction. This of course can be done but not without increasing the speed of the item in relation to the belt. This of course is not possible with our aircraft because the speeds are matched in the original question.
No airspeed = no take-off with conventional aircraft. What have I missed?
Errrmmmmm ... The entire thread it would appear
Or, when God was giving out heads you thought he said beds and asked for a nice thick fluffy one
Just to save you actually reading the thread there's something you may like to consider ... Aircraft don't need ground speed to take off, its airspeed that counts
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possibly because the conveyor is a trick question.
if you had a car (driven by its wheels) then the car's movement through space depends on the rotation of the wheels against the road. If the road was moving forward, the cars speed would increase, if it was moving backward, the car's speed would decrease.
Most of us are used to cars and roads and the question tricks us into applying the same thought process to the plane question.
However the plane's movement is not driven by the wheels, so it is a trick question.
The airspeed of the aircraft isn't measured in relation to the belt its measured in relation to a fixed point not on the belt ... Once you've grasped this one you'll have seen the light and be on your way to take off velocity
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The airspeed of the aircraft isn't measured in relation to the belt its measured in relation to a fixed point not on the belt ... Once you've grasped this one you'll have seen the light and be on your way to take off velocity
It wont be measuring anything as the plane wont be going anywhere
it also seems to me that
"This conveyor belt has a control system that tracks the aircraft's wheels speed and tunes the speed of the conveyor belt to be exactly the same as the wheels, but in the opposite direction. There is no wind. The pilot begins to add thrust to the engines..."
doesn't work for an aircraft. If the aircraft was moving through the air at even 1mph, the wheels would be rotating at 1mph so the conveyor would move at 1mph the other way. But the aircraft is still moving through space at 1mph so the wheels are turning at 2mph (1mph movement plus 1 mh conveyor). So the conveyor moves at 2mph. But the plane is moving forward at 1mph so the wheels are turning at 3mph. So the conveyor move at 3mph to counteract it. But the plane is moving at 1mph through space so the wheels are turning at 4mph. So the conveyor moves at 4mph. But the plane is moving through space at 1mph so the wheels are tuning at 5mph.... etc
So it seems to me that for any forward movement of the plane greater than zero, the conveyor must move at infinite speed. The question cannot become realistic. It is a question that can be applied to a vehicle driven by its wheels but cannot be applied to a vehicle that moves through any other means.
"This conveyor belt has a control system that tracks the aircraft's wheels speed and tunes the speed of the conveyor belt to be exactly the same as the wheels, but in the opposite direction. There is no wind. The pilot begins to add thrust to the engines..."
doesn't work for an aircraft. If the aircraft was moving through the air at even 1mph, the wheels would be rotating at 1mph so the conveyor would move at 1mph the other way. But the aircraft is still moving through space at 1mph so the wheels are turning at 2mph (1mph movement plus 1 mh conveyor). So the conveyor moves at 2mph. But the plane is moving forward at 1mph so the wheels are turning at 3mph. So the conveyor move at 3mph to counteract it. But the plane is moving at 1mph through space so the wheels are turning at 4mph. So the conveyor moves at 4mph. But the plane is moving through space at 1mph so the wheels are tuning at 5mph.... etc
So it seems to me that for any forward movement of the plane greater than zero, the conveyor must move at infinite speed. The question cannot become realistic. It is a question that can be applied to a vehicle driven by its wheels but cannot be applied to a vehicle that moves through any other means.
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I agree with you Joe ... There, I've said it now
So does Softus and many others.
Perhaps we should just start abusing Blondini, FarmerTwit & Co and get the thread locked.
I'll leave this one to you, you're better at it than me
So does Softus and many others.
Perhaps we should just start abusing Blondini, FarmerTwit & Co and get the thread locked.
I'll leave this one to you, you're better at it than me
At which point of course the belt is running at 360 mph in the other direction and the resulting airspeed is zero......
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