Fundamental Frequency of Vibrating String: From 256Hz to ?Hz

[hoyy1kolko]

Homework Statement

The fundamental frequency of a vibrating stretched string of length 1.0m is 256Hz.When the string is shortened to 0.4m with the same tension,the fundamental frequency now become
how many Hz?

Homework Equations

The Attempt at a Solution

 

[gneill]

No attempt, no help!

 

[supratim1]

attempt using basic equations. check your theory book once again.