What is the natural frequency of a sonometer wire under tension ?
Answers
→ What is The natural frequency of a sonometer wire under some tension ?
=> The natural frequency of a sonometer wire under tension is given by the formula :
Where
↪ T is the tension of the wire
↪m is the mass per unit length of the wire
↪ l is the length of the wire between the bridges
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Explanation:
ANSWER :–
new frequency – $$\begin{lgathered}{ \boxed { \bold { {n}_{1} = \frac{n}{4} }}} \\\end{lgathered}$$
EXPLANATION :–
GIVEN :–
• The fundamental frequency of a sonometer wire is n.
• The length and diameter of the wire are doubled keeping the tension same.
TO FIND :–
New fundamental frequency = ?
SOLUTION :–
• We know that frequency –
$$\begin{lgathered}\\ { \boxed { \bold { n = \frac{1}{2l} \sqrt{ \frac{T}{m} }}}} \\\end{lgathered}$$
• Mass per unit Length :–
m = [ρΠr²(l)]/l
m = ρΠr²
• So that , new equation –
$$\begin{lgathered}\\ { \boxed { \bold { n = \frac{1}{2(2l)} \sqrt{ \frac{T}{ \rho \pi {(2r)}^{2}}}}}} \\\end{lgathered}$$
• Now According to the question –
Length (l) => 2l and radius (r) => 2r
• New fundamental frequency –
$$\begin{lgathered}\\ { \bold { {n}_{1} = \frac{1}{2(2l)} \sqrt{ \frac{T}{ \rho \pi {(2r)}^{2}} }}} \\\end{lgathered}$$
$$\begin{lgathered}\\ { { \bold { {n}_{1} = \frac{1}{4l} \sqrt{ \frac{T}{4 \rho \pi {r}^{2}} }}}} \\\end{lgathered}$$
$$\begin{lgathered}\\ { { \bold { {n}_{1} = \frac{1}{2(4l)} \sqrt{ \frac{T}{ \rho \pi {r}^{2}} }}}} \\\end{lgathered}$$
$$\begin{lgathered}\\ { { \bold { {n}_{1} = \frac{1}{4} {n} }}} \\\end{lgathered}$$
$$\begin{lgathered}\\ { { \bold { {n}_{1} = \frac{n}{4} }}} \\\end{lgathered}$$