Check carefully whether a graph is a speed-time graph or a distance-time graph. On true speed–time graphs, the speed has only positive values. On velocity–time graphs the velocity can be negative. Image Tachographs are instruments that are put in lorry cabs to check that the lorry h...
Wavelength is the distance from one compression to the next in a sound wave. The frequency is how many wavelengths pass by is a set amount of time. These two elements always exist with sound waves, so they are a vital part of determining the speed, or velocity, of sound. In order to...