Solving the Mystery: Plane of Reference Question

AI Thread Summary
When a bullet train accelerates to 200 km/hr in 3.5 seconds, the toy helicopter inside will generally hover relative to the train if the acceleration is gradual, as the air in the compartment will move with the train. The helicopter relies on the air for support, which is pushed by the back wall of the train, allowing it to stay in place. However, if the train's acceleration is too rapid, the helicopter could be affected by inertia and potentially crash. In contrast, if the helicopter were in an open vehicle like a jeepney, it would likely crash against the back wall due to the lack of air containment to carry it along. The discussion highlights the importance of acceleration rates and environmental factors in determining the helicopter's behavior.
Handsome jack
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I saw random question somewhere on the internet a couple of weeks ago and it got me really thinking about it.

Supposedly you got a remote control miniature toy helicopter hovering inside a bullet train, if the bullet train suddenly started and accelerated to 200km/hr in 3.5 sec, will the toy helicopter hover with respect to the moving train or will it crash somewhere inside the train?
 
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Handsome jack said:
200km/hr in 3.5 sec,
How many "g?" How many "g" can the toy handle?
 
Handsome jack said:
I
Supposedly you got a remote control miniature toy helicopter hovering inside a bullet train, if the bullet train suddenly started and accelerated to 200km/hr in 3.5 sec, will the toy helicopter hover with respect to the moving train or will it crash somewhere inside the train?

When the train accelerates, the back wall of the compartment will push on the air in the compartment, very quickly bringing it up to speed. (That's why you don't feel any wind when you're sitting in a closed compartment in a moving train - you, the air, and the train are all moving at the same speed).

The toy helicopter is supported by the air, so it's going to do whatever the air is doing. If the acceleration of the train is reasonably slow, the helicopter will just be carried along with the air as it keeps up with the train. If the acceleration of the train is high enough, more interesting things can happen, but that will depend on the specific numbers involved.

You might try comparing this case with the behavior of a pencil resting on a table on the train. If the train accelerates or decelerates sharply enough the pencil will be thrown off the table, but if the acceleration is more gradual the pencil will stay put as it, the table, and the pencil all speed up. The helicopter is being accelerated by the force of the air on it and the air is accelerating because it's being pushed by the back wall of the compartment; the pencil is being accelerated by the force of friction between it and the table, and the table is being accelerated because it's fastened to the accelerating train.
 
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Nugatory said:
When the train accelerates, the back wall of the compartment will push on the air in the compartment, very quickly bringing it up to speed. (That's why you don't feel any wind when you're sitting in a closed compartment in a moving train - you, the air, and the train are all moving at the same speed).

The toy helicopter is supported by the air, so it's going to do whatever the air is doing. If the acceleration of the train is reasonably slow, the helicopter will just be carried along with the air as it keeps up with the train. If the acceleration of the train is high enough, more interesting things can happen, but that will depend on the specific numbers involved.

You might try comparing this case with the behavior of a pencil resting on a table on the train. If the train accelerates or decelerates sharply enough the pencil will be thrown off the table, but if the acceleration is more gradual the pencil will stay put as it, the table, and the pencil all speed up. The helicopter is being accelerated by the force of the air on it and the air is accelerating because it's being pushed by the back wall of the compartment; the pencil is being accelerated by the force of friction between it and the table, and the table is being accelerated because it's fastened to the accelerating train.

What would happen if it was in another vehicle with the windows open or something similar? perhaps a jeepney
 
Handsome jack said:
What would happen if it was in another vehicle with the windows open or something similar? perhaps a jeepney
What do you think and why?
 
Nugatory said:
What do you think and why?
well in my opinion perhaps the back windows are open, the toy copter would hover in the same place leaving it outside while the jeepney moved forward since there is no contained in the jeepney that would move it with respect to the vehicle since it's an open type of vehicle
 
The helicopter would most likely crash against the back wall.
 

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