Question

Imagine making waves on a slinky. First, we make a wave with: wavelength 2 cm long, amplitude 0.2 cm, Frequency at 1 Hz and wave speed of 2 cm/s.

If we then shake the slinky twice as often, what happens to the wavelength, amplitude, frequency and wave speed?

Answer 1

Frequency will be doubled:

$$f'=2f=2(1)=2\ Hz$$

The wave speed will be the same:

$$v'=v= 2\frac{cm}{s}$$

The wavelength will be:

$$\lambda'=\frac{v}{f'}=\frac{2}{2}=1\ cm = \frac{1}{2} \lambda$$

The amplitude will be the same:

$$A'=A=0.2 \ cm$$