- #1
AJKing
- 104
- 2
Homework Statement
This is from A.P. French, Vibrations and Waves, Problem 3-7
A wire of unstretched length l0 is extended by a distance of 10-3l0 when a certain mass is hung from its bottom end. If this same wire is [turned to be horizontal] and the same mass is hung from the midpoint of the wire [...], what is the depression y of the midpoint, and what is the tension in the wire?
Homework Equations
[itex]F = -\frac{AY}{l_0}*x[/itex]
[itex]F = k*x[/itex]
[itex]k = -\frac{AY}{l_0}[/itex]
The Attempt at a Solution
The correct answer is y = l0 / 20
and T = 5 * mg
I have not recreated these solutions.
I have two triangles to consider:
one of lengths, with base l0/2, height y and hypotenuse l0 + x
one of Forces, with base Ti, height mg/2 and hypotenuse T = -\frac{AY}{l_0}*x
I've tried a lot of things. I'm missing something fundamental.
If you can get the correct answer, I would appreciate a little direction.