A longitudinal standing wave can be created in a long, thin aluminum rod by stroking the rod with very dry fingersThis is often done as a physics demonstration, creating a high-pitched, very annoying whineFrom a wave perspective, the standing wave is equivalent to a sound standing wave in an open-open tubeIn particular, both ends of the rod are anti-nodes.What is the fundamental frequency of a 1.90 m-long aluminum rod?
Go to your local Hardware or big box hardware like Lowe'sThe people who work there can inform you what to get but I know for sure it isn't gonna be pvc.
f v / 2 L ; where v speed of sound So we need to find the speed of sound in aluminumSee second web sitef (4877 m/s) / (2?1.90m) f 128.2 s^-1 128.2 Hz
before you paint you need to address why there is moisture in the first placeit is not there just from your use of the bathroom you need to check under the house odds are there is the problem if you paint now and dont take care of the moisture your just throwing away money common problem is the toilet it may be leaking just under the ground if it is extremely wet under therelot of proswant to lay plastic down DO NOT ALLOW THIS it will just trap moisture if the mold is bad under the home then salt is your best option salt from a water softener as it dissolves it will ruin the water for any pest living off of it and as the water evaporates it will adhere to the wood and leaving trace amounts of salt this salt will kill the mold if you can afford rock salt for thaw even betteri have seen many rooms get ruined due to moisture not being located there is a cheep way to help out the studs are 16 in apart centerdrill about a 1 in hole at the top of the wall in between each stud and leave it open this will allow air into the wall and aid it in drying and if you dont like the holes can cover with wood trim just make sure not to cover the hole fully will need a gap there is no insulation on interior walls and the reason is due to moisturebut most showers are on the outer wall and there is insulation it will collect moisture and it takes forever to dry better homes built today have holed drilled so that the air can flow from under the house up into the attic but i would not do this unless screen was addedif this moisture leads into the ceiling you should remove the insulation from its spot till it dries some of the egg cartons laid under the insulation before placing it back will help .
