#digipen/phy250 Homework 3
#### 2
A fisherman's scale stretches 3.9 cm when a 2.9-kg fish hangs from it.
$ \begin{align}
-3.9 k + 2.9g &= 0 \\
\frac{2.9g}{3.9} &= k\\
\frac{2.9 \cdot 9.81}{3.9} &= k \\
k &= 7.3 \,{\op{N}\op{cm}^{-1}} \\
&= 730 \,{\op{N}\op{m}^{-1}} \\
\end{align}$
![[../00 Asset Bank/Pasted image 20250922132510.png]]
What will be the frequency of oscillation if the fish is pulled down 3.4 cm more and released so that it oscillates up and down?
$\begin{align}
y(0) &= 3.9 + 3.4=7.3\\
y'' & = 2.9g - 7.3y \\
y &= A\cos( \omega t+\phi) + B \\
y&= 3.4 \cos(\omega t) + 3.9 \\
y'&= 3.4 \omega (-\sin \omega t) \\
y'' &= -3.4 \omega^2 \cos(\omega t)\\
-3.4 \omega^2 \cos(\omega t) &= 2.9g - 7.3\pa{ 3.4 \cos(\omega t)+3.9} \\
-y-3.9 &= 2.9g - 7.3y \\
6.3y &= 2.9g + 3.9 \\
y&= 2.9g + 3.9 \\
\end{align}$