Perhaps this is a very naive question. If that is the case, I apologise.(I would still like to hear your answer ).
Assume that I took the end of a very long string and moved it up and down. A number of waves are generated.
My question is, why are they formed? I know that this is a way of propagating energy. But, why does it do that in this manner?
I mean, why is it not like a standing wave? ie. The disturbance causes the particles at the end to oscillate up and down and further disturbances solely affect these oscillations. (The energy I give by moving the end of the string is responsible for these oscillations ). Why do these disturbances travel in a particular direction?
Another question is, when I hit a drum using a stick, that sound is heard by a person standing far behind. Why? I mean, if the diaphragm was situated in the vertical direction perpendicular the ground , shouldn't only the region of air situated infront of the air undergo compression and rarefaction and consequently, shouldn't only a person standing infront of the drum hear that sound?