Question

If stretching force T and length L of a wire is doubled then its frequency
a)decrease by 2 times
b)increase by 2 times
c)decrease by 4 times
d)increase by 4 times ​

Answer 1

answer : option (b) increase by 2 times.

explanation : frequency of progressive wave in a stretch string is given by,

$f=k\sqrt{\frac{T}{\mu}}$

where k is proportionality constant, f is frequency,T is tension in string and μ is linear mass density of string.i.e., μ = m/L, where m is mass of string.

a/c to question,

stretching force T and length L of a wire is doubled.

so, T' = 2T and μ' = m/2L = μ/2

then, f' = k√{2T/μ/2} = 2k√{T/μ} = 2f

hence, frequency becomes double of its initial value.

Answer 2

Explanation:

increase by 2 times ❣️❣️❣️❣️❣️