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morrisj753
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Homework Statement
A point object of mass M hangs from the ceiling of a car from a massless string of length L. It is observed to make an angle θ from the vertical as the car accelerates uniformly from rest. Find the acceleration of the car in terms of θ, M, L, and g.
Diagram: http://www.aapt.org/physicsteam/2010/upload/2010_FmaSolutions.pdf (Number 9)
Homework Equations
F = ma
The Attempt at a Solution
They wanted the acceleration, so I started with
a = F / m
The only thing I need is to find F and substitute it back into the above equation. However, I don't know if the car is moving up an inclined plane or on a horizontal surface.
If it were a horizontal surface, the only force would be mg sin θ (mg cos θ and Fn (ceiling) would cancel each other out), so a = g sin θ, which is not correct. My thinking is obviously flawed, so any ideas would be helpful.
Thank you