Given:
The length of the slinky is: L = 4 m.
The time taken by the wave to travel the length and back again is: t = 4.97 s
To find:
a) The speed of the wave
b) The frequency of the wave
Step-by-step explanation:
a)
As the wave on the slinky travels along the length and back again, it covers a distance that is double the distance of the slinky.
Thus, the total distance "d" traveled by the wave will be 2L.
The speed "v" of the wave is given as:
![\begin{gathered} v=(d)/(t) \\ \\ v=(2L)/(t) \end{gathered}](https://img.qammunity.org/2023/formulas/physics/college/akr65z2u2uwxi53db2ytdm7d0y1r3t141o.png)
Substituting the values in the above equation, we get:
![\begin{gathered} v=\frac{2*4\text{ m}}{4.97\text{ s}} \\ \\ v=\frac{8\text{ m}}{4.97\text{ s}} \\ \\ v=1.61\text{ m/s} \end{gathered}](https://img.qammunity.org/2023/formulas/physics/college/9va7vxxynqxz2yk28iyvva58fa1qovhmbg.png)
Thus, the speed of the wave is 1.61 m/s
b)
The standing wave created consists of seven antinodes and eight nodes. Thus, the length of the slinky is 7/2 times the wavelength of the wave.
![L=(7)/(2)\lambda](https://img.qammunity.org/2023/formulas/physics/college/20hv349zb5igf4jypknmwi07fqguqv8mzb.png)
Rearranging the above equation, we get:
![\lambda=(2)/(7)L](https://img.qammunity.org/2023/formulas/physics/college/93c9b8c2wl6hdfpib5eey77tzrl3wm6c47.png)
Substituting the values in the above equation, we get:
![\lambda=(2)/(7)*4\text{ m}=\frac{8\text{ m}}{7}=1.143\text{ m}](https://img.qammunity.org/2023/formulas/physics/college/zypzqnnrqoqnne0vr296abw9qx38b007mi.png)
The speed "v" of the wave is related to its wavelength "λ" and a frequency "f" as:
![v=f\lambda](https://img.qammunity.org/2023/formulas/physics/high-school/jl8nf6bt8lf9pxiy3380yrsx3nzm2gk95h.png)
Rearranging the above equation, we get:
![f=(v)/(\lambda)](https://img.qammunity.org/2023/formulas/physics/high-school/puugc9221m5n0c13uxcss75flkr0bngwjo.png)
Substituting the values in the above equation, we get:
![\begin{gathered} f=\frac{1.61\text{ m/s}}{1.143\text{ m}} \\ \\ f=1.41\text{ Hz} \end{gathered}](https://img.qammunity.org/2023/formulas/physics/college/965hhbaxu5nqecuorw7drwadspt2ggkti2.png)
Thus, the frequency of the wave on the slinky is 1.41 Hz.
Final answer:
a) The speed of the wave is 1.61 m/s.
b) The frequency of the oscillation of the slinky is 1.41 Hz.