Two identical strings, of identical lengths of 2.00 m and linear mass density of μ=0.0065kg/m, are fixed on both ends. String A is under a tension of 120.00 N. String B is under a tension of 130.00 N. They are each plucked and produce sound at the n=10 mode. What is the beat frequency?

Respuesta :

Answer:

beat frequency = 13.87 Hz

Explanation:

given data

lengths l = 2.00 m

linear mass density μ = 0.0065 kg/m

String A is under a tension T1 = 120.00 N

String B is under a tension T2 = 130.00 N

n = 10 mode

to find out

beat frequency

solution

we know here that length L is

L = n × [tex]\frac{ \lambda }{2}[/tex]      ........1

so  λ = [tex]\frac{2L}{10}[/tex]  

and velocity is express as

V = [tex]\sqrt{\frac{T}{\mu } }[/tex]    .................2

so

frequency for string A = f1 = [tex]\frac{V1}{\lambda}[/tex]

f1 = [tex]\frac{\sqrt{\frac{T}{\mu } }}{\frac{2L}{10}}[/tex]

f1 = [tex]\frac{10}{2L} \sqrt{\frac{T1}{\mu } }[/tex]      

and

f2 = [tex]\frac{10}{2L} \sqrt{\frac{T2}{\mu } }[/tex]

so

beat frequency is = f2 - f1

put here value

beat frequency = [tex]\frac{10}{2*2} \sqrt{\frac{130}{0.0065}}[/tex]  - [tex]\frac{10}{2*2} \sqrt{\frac{120}{0.0065} }[/tex]

beat frequency = 13.87 Hz