Showing posts with label sound. Show all posts
Showing posts with label sound. Show all posts

Sunday, July 26, 2020

Sounds that can kill - Introduction to sonic weapons


man pointing weapon

In physicssound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid. It is a form of energy. But is this energy comparable with the energy produced by modern day weapons??.....


A weapon is anything which causes physical damage to the target, usually this damage is caused by delivery of energy in different forms like heat,and kinetic, etc Weapons mostly rely on the concept of impact collision of energy on the target .


Most conventional weapons rely on chemical energy (explosives) as their destruction mechanism, either to explode on target, like bombs, or to create kinetic energy, like a bullet. 


The chemicals in the weapons are ignited to convert the chemical energy to other forms of energy. A chemical weapon attack occurs in two phases: delivery and dissemination. The delivery phase refers to the launching of the rocket, bomb, or artillery shell. 


The dissemination phase involves the dispersal of the chemical agent from the weapon. Chemical via a variety of mechanisms including but not limited to; ballistic missiles, air dropped gravity bombs, rockets, artillery shells, aerosol canisters, land mines, and mortars.


 There are another type of weapons in which they use stored electrical energy as their source, called as electrical weapons obviously. Electric weapons generally fall into two categories: directed-energy weapons (DEWs) and electromagnetic (EM) launchers.


 DEWs send energy, instead of matter, toward a target, and can be separated into three types: laser weapons, particle-beam weapons, and high-power microwave (HPM) or radio-frequency (RF) weapons. EM launchers use electrical energy to throw a mass at a target, thus making them distinct from directed energy.

 

Then comes sonic weapons, as we know sound is also a form of energy, these weapons use sound energy(vibrations) as their source. Sound in specific range of frequencies have different effects. Sound is mainly categorised in three types based on the frequencies. 1. Infra sound (0-20Hz),  2. Audible range(20-20,000Hz),  3. Ultrasonic(>20,000Hz). 


The sound we mostly hear is in the audible range only. It is observed the ultrasonic sound waves can cause discomfort among humans like nausea, vomiting, dizziness, etc. Many a times such sound emitters have also been used for crowd controlling by the US. 


One more interesting incident is the attack on US embassy in Cuba, where almost all the staff experienced similar symptoms at the same week accompanied by a chirping sound. While the  reason behind this is not clear, experts believe that it may be an attempt to use sonic weapons.

 

The Long Range Acoustic Device (LRAD) which produces a 30 degree cone of audible sound in frequencies within the human hearing spectrum (20 Hz - 20 kHz) is mostly used to broad cast long range audible signals, mostly by navy, government officials, etc.

 

An LRAD was used by the crew of the cruise ship Seabourn spirit in 2005 to deter Pirates who chased and attacked the ship. More commonly this device and others of similar design have been used to disperse protesters and rioters in crowd control efforts.

 

Another sound factor is power, usually described using a unit of measurement called a decibel. Decibels are used to measure the power of audible and inaudible sound, both of which produce effects. 


Any sound begins to become physically painful at about 120 decibels, although at lower levels it can cause discomfort. At about 130 decibels it becomes unbearable. Prolonged exposure of high power sound such as that of large speakers in an event can cause damage to our eardrums in some cases the damage can be permanent.

 

High power sound waves can also damage the target if impacted on them. The phenomenon of resonance can also be used to design such weapons. One can make any target resonate with the help of the weapon(say resonator weapon), which will cause physical damage to the target. 


One can easily see the damage caused by resonance when an opera singer can break a wine glass. If one could make ..Say any vehicle resonate through the weapon, just as the singer makes the glass to resonate, this can prove a ground breaking invention. While research is still going on this field and the way to design weapon, these can change the whole scenario  of modern combats.

 

This still being introduction for this topic, we shall work on developing this concept. We will introduce advanced articles on this topic where we will discuss about the weapons in detail.  One can suggest their ideas in the comments, we are all ears.

 

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