What Angle Does a Bob in an Accelerating Train Make with the Vertical?

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The problem involves a bob suspended in a train accelerating at g/√3. An observer inside the train will see the bob at a 30-degree angle from the vertical due to the pseudo force acting on it. An observer on the platform will also perceive the bob at a 30-degree angle, as the alignment of the rope remains consistent regardless of the observer's position. Both observers agree on the angle because the rope's alignment does not change, despite one potentially obscuring the view of the angle measurement. Thus, the angle observed by both is the same.
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Homework Statement


A bob of mass m is suspended from the ceiling of a train moving with an acceleration g/√3
(a) If an observer is sitting inside the train, what angle with the vertical will he observe?
(b) If an observer is standing on the platform, what angle will he observe?

Homework Equations

The Attempt at a Solution


I know that the angle is 30 degrees (after taking the pseudo force into account), but I'm not sure if this is the answer for both parts or just (b)?
 
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If there is a protractor sticking down from the train's ceiling, will the 2 observers agree with the rope's alignment?
 
I don't know, that's the issue.
 
One guy sees the rope in front of (obscuring) the 30° mark ... how could the other guy see a different number being blocked?
The light either gets blocked, or it doesn't.
 
So they both see the same thing. Okay!
 

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