On Fig. 4.1, finish the two graphs so that they show the meaning of amplitude $A$, wavelength $\lambda$ and period $T$ for a progressive wave. Make sure each graph has its axes labelled.
A horizontal string is fixed between two points $X$ and $Y$. A vibrator makes the string oscillate so that a stationary wave is produced. The speed of a progressive wave on the string is $30\,\text{m s}^{-1}$. The stationary wave has a period of $40\,\text{ms}$. Explain how the stationary wave is formed on the string.
A particle on the string oscillates with an amplitude of $13\,\text{mm}$. At time $t$, the particle has zero displacement. Calculate the displacement of the particle at time $(t + 100\,\text{ms})$.
Calculate the total distance moved by the particle from time $t$ to time $(t + 100\,\text{ms})$.
Determine the frequency of the wave.
Determine the horizontal distance from $X$ to $Y$.