Functions Of The Telescope -Most people would say that the main function of a

telescope is to make things look larger. But in fact, the most important function is

to make things look  brighter!  This is called its  light-gathering power. If you

enlarge an object, it gets fainter because you are spreading the light over a

larger image, so any telescope has a limit to how much magnification it can

comfortably deliver. Another important function of the telescope is  resolving

 po wer. Th is measu res ho w well yo u can se pa rat e two obj ects , and of co ur se th is is

related to how sharp the image looks.  

Both of these functions, light gathering power and resolving power, depend only

on the size of the telescope (called theaperture). The light gathering power

depends on the area of the main element (the objective), while the resolving

 po wer de pe nds on th e diam et er .

Periscope-The periscope is used primarily to view the surface of the water around

the submarine, as well as to transmit Morse code messages to other subs or ships

in the vicinity.(vicinity means a nearby surrounding.)

Ultrasound Scanning Device –Firstly you must know the meaning of ultrasound

before knowing about the scanning device.  Meaning - Ultrasound is an oscillating

sound pressure wave with a frequency greate r than the upper limit of the human

hearing range. Ultrasound is thus not separated from 'normal' (audible) sound

based on differences in physical properties, only the fact that humans cannot hear

it. The device - Ultrasonics is the application of ultrasou nd. Ultrasound can be

used for medical imaging, detection, measur ement and cleaning. At higher power

levels, ultrasonics is useful for changing the chemical properties of substances.

 x- ra y Ma chine -[Used for medical function, airport scanner and astronomy] to

examine several parts of the body and to treat conditions./ To see broken parts of

the body such as bones and detect fractures that can't be seen by a naked eye. /  

The medical community uses X-rays to examine several parts of the bo dy and to

treat conditions. "Imaging with X-rays involves exposing a part o f the body to a

small dose of ionizing radiation to produce pictures of the inside of the body,"

according to the Radiological Society of North America. The denser the material,

the more X-rays it will absorb an d later appear white in the picture. For example,

bones and teeth, which are both dense, show up white, while lungs that contain

lots of air show up as black. Muscle and fat appear gray. Skin absorbs few X -rays,

making it appear transparent and enabling the dentist to get a good view of a

 pa tie nt 's te et h. Be ca us e me ta l ab so rb s th e mo st X-r ay s, th e de nt is t ea si ly sp ot s

 fi ll ing s in te et h. Phy sic ia ns us e X-ra ys to de te ct br ok en bo ne s, joi nt di sl oc at io ns ,

spinal fusions, abnormal bone growths, arthritis and bony changes seen in

 

metabolic conditions. They also use it to detect swallowed objects, to examine

breast tissue, to evaluate infections and cancerous conditions in the chest, to

highlight the circulatory system and to check for enlarged hearts. Doct ors treat

certain cancers with a high frequency X-ray in a procedure called radiotherapy.

Hearing.

Stethoscope- Stethoscopes are used to monitor and listen to the rythmn of your

heart and lungs. also it is used to moniter tree growth and the growth of some

 fu ngi.  [Weird Fact] a stethoscope can be used as a weapon to defend yourself

 fr om enem y pe op le and fu ng i by sw ingin g it in a ni nj a li ke wa y. st et ho scop es we re

 fi rst di scovered on th e ma y fl ow er by Ol li e Sy ke s wh o used it to catc h fi sh .

Microphone-  A microphone is an acoustic-to -electric transducer or sensor that

converts sound into an electrical signal. Microphones are used in many

applications such as telephones, tape recorders, karaoke systems, hearing aids,

motion picture production, live and recorded audio engineering, FRS radio s,

megaphones, in radio and television broadcasting and in computers for recording

voice, speech recognition, VoIP, and for non -acoustic purposes such as ultrasonic

checking or knock sensors.

Most microphones today use electromagnetic induction (dynamic microphone),

capacitance change (condenser microphone), piezoelectric generation, or light

modulation to produce an electrical voltage signal from mechanical vibration .

Electronic Hearing Aid-  A he ar in g aid is an el ectro acous ti c dev ice wh ich is

designed to amplify sound for the wearer, usually with the aim of making speech

more intelligible, and to correct impaired hearing as measured by audiometry. In

the United States, Hearing aids are considered medical devices and are regulated

by the Food and Drug Administration (FDA). Ordinary small audio amplifiers or

other plain sound reinforcing systems cannot be sold as "hearing aids".

Earphone-  Headphones are a pair of small loudspeakers that are designed to be

held in place close to a user's ears. They are also known as earspeaker s,

earphones or, colloquially, cans. The alternate in -ear versions are known as

earbuds or earphones. In the context of telecommunication, a headset is a

combination of headphone and microphone. Headphones either have wires for

connection to a signal source such as an audio amplifier, radio, CD player,

 po rt ab le me dia pl ay er, mo bil e pho ne , el ectron ic mu sical in st ru me nt , or have a

wireless device, which is used to pick up signal without using a cable.