A sonometer wire of length l vibrates in fundamental mode when excited by a tuning fork of frequency 416 Hz. If the length is doubled keeping other things same the string will
Where 
is the length 
tension
Hence, 
Plugging in the values, we get
1
A sonometer wire of length l vibrates in fundamental mode when excited by a tuning fork of frequency 416 Hz. If the length is doubled keeping other things same the string will
Where is the length tension
Hence,
Plugging in the values, we get