help me with this, please?

Question

The A string on a string bass is tuned to vibrate at a fundamental frequency of 51.0 Hz. If the tension in the string were increased by a factor of 3, what would be the new fundamental frequency?

Answer 1

f=1/2L sqrt (T/u)
where
f is frequency
T is the tension,
u is the linear mass,
L is the length of the vibrating part of the string.
We have
51.0 Hz=1/2L sqrt (T/u)
let k=1/2L sqrt (1/u)
Then 51.0 Hz=ksqrt(T)
f3/51.o=k sqrt(3T)/ k sqrt(T)/
f3=51.0 sqrt(3)
f3= 88.3 Hz