Energy of Oscillations: Find Work Done Against Tension

[anubis01]

Homework Statement

A string of length L is clamped at both ends, pulled up a distance h with tension T. What is the energy of the subsequent oscillations after plucking. [Hint, consider the work done against the tension in giving the string its initial deformation]

Homework Equations

E=K+U

The Attempt at a Solution

I'm not completely sure if my answer is correct or not, so if anyone can help me check it I would greatly appreciate it. I also just scanned my work because I'm not that great at using the forums latex commands.

http://img242.imageshack.us/img242/1155/cci24092009800000i.jpg

 

[turin]

That seems to be correct.

In order to use the hint, you first need to figure out what is the force required to hold the string at a (small) displacement y (using small angle approximations). Then, the work is the integral of this force from y=0 to y=h. Doing this, you will get the same answer.

BTW, good job with all those pesky factors of 2. I always screw those up.

 

[anubis01]

That seems to be correct.

BTW, good job with all those pesky factors of 2. I always screw those up.

yeah those factors of 2 tricked me up for a while too. Thanks for the help, its much appreciated.