Question

1.   A standing wave has a frequency of 324 HZ.  It is vibrating in 4 sections.  Calculate the velocity of the wave if the length is 3 metres.  L=n λ/2   (/2)

  

 

 

 

B.  If the length of the string was shortened to 2 metres, determine the period of the wave?  (/2)

 

 

 C.  Determine the fundamental frequency (n=1) for both lengths of string.  (/2)

Answer 1

Gives

Frequency (n)=324Hz

Section=4

We know that

$L=\frac{n\lambda}{2}$

$L=3m$

$\nu=324Hz$

n=3

$\lambda=\frac{2\times3}{3}=2m$

$v=\nu\lambda$

Put value

$v=324\times2=648m/sec$

Part(2)

Length(l)=2m

$v=\frac{\lambda}{T}$

$T=\frac{\lambda}{v}$

$L=\frac{n\lambda}{2}$

$2=\frac{1 \times\lambda}{2}$

$\lambda=4m$

$T=\frac{4}{648}=0.0061sec$

Part(3)

When n=1 ,$\lambda=6m$

$\nu=\frac{v}{\lambda}=\frac{648}{6}=108Hz$

n=1,$\lambda=4m$ $,l=2m$

$\nu=\frac{v}{\lambda}$

V=491m/sec

$\nu=\frac{491}{2}=245Hz$