Triangles Can be Solved Using: 1  Pythagoras's Theorem. 2  Sine Rule. 3  Cosine Rule. 4  Angles all add up to 180 degrees.
Report Abuse. sound travels fastest in solid substances. as in solids, the medium is denser and it aids the propogation of sound. sound will not travel in vaccum as they will not propogate if no material medium is present. in air it travels with the speed of 350 m/s which is less than the speed of sound in solids.
This is because the speed of sound waves depends upon the material through which they are travelling. Sound travels 15 times faster through the metal railway tracks than through air, giving the cowboy an early warning of the train's arrival. How much plainer could it be? I, personally, had never thought of it that way. I love this illustration.