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Train Door - how long does it take to close?
A train accelerates from rest at a constant acceleration A. If a door of width L is open perpendicularly to the train as the train begins to accelerate, how long does the door take to close? (assume the door closes in the direction opposite to the train's motion).
second answer i think has the right idea but it is not simple to evaluate because angular acceleration is not constant. third answer i think does not address the swinging of the door shut, more of a linear analysis
2 Answers
- Anonymous8 years agoFavorite Answer
Insufficient information.
- 8 years ago
first , i will give u the hint to solve the problem ,
the door will get the spseudo force which will produce torque , and that will creat angular acelaration ,get the value of anglular aclleration , use one of kinematic equation as the angular displacement is pie/2 initial angular velocituy is zero , u have got the anular acelaration , finally u will get the time
