sainstechnological devices which are suitable for overcoming the limitations of sight and hearing
DESCRIPTION
Science Form 2,Chapter 1TRANSCRIPT
Title of the project:
Technological devices which are suitable for overcoming the
limitations of sight and hearing
NAME : NUR ATHIRAH BT MD YUSUF
CLASS : 2 AL-KHAZIN
TEACHER : PUAN. SURIA
NOMAK : 113/010
Humans have sight and hearing limitation. Without any devices, our sight
and hearing was limited. Most of the limitation of sight can be overcome with the help of certain optical instruments such as magnifying glass, microscope,
binoculars and others. The range of frequency of hearing in human 20 Hz to 20 000 Hz. It was different according to the age of a person. Hearing limitations can be overcome by using devices such as microphone, stethoscope, earphone
and PA system. All of these devices help us to make our live easier.
DEVICES USED TO OVERCOME THE LIMITATIONS OF SIGHT
objective of the project
understanding light and sight
state the devices used to overcome the limitation
of sight
Op ti cal Il lu si on
WHAT WE SEE DEPENTS NOT ONLY ON YOUR EYES ,BUT ALSO
ON YOUR BRAIN .SOMETIMES THE BRAIN DISTORTS IMAGES .THIS
GIVES RISE TO OPTICAL ILLUSION.THE IMAGE FORMED IN THE EYE IS ACCURATE BUT THE BRAIN PLAYS A TRICKS ON US
AND MAKES THE IMAGE MISLEADING.
The blind spot
WHEN IMAGES FALL ON THE BLIND SPOT,THEY CANNOT BEEN SEE.THIS IS BECAUSE
Limitation of sight for human
blind spot
cannot see
through opaque objects
not able to see too
tiny objects
optical illusion
not able to see too
distant objects
CHARACTERISTIC
STEREOSCOPIC VISION
MONOCULAR VISION
FIELD OF VISION
OVERLAPPING VISUAL FIELD
OVERLAP HAVE A LITTLE OR NO OVERLAPPING
ADVANTAGES
1.EACH EYE SEES A SLIGHTLY DIFFERENT IMAGE
2.TO JUGDE DISTANCE ACCURATELY
1.HAVE A WIDE FIELD OF VISION
2.DETECTS THEIR ENEMIES FROM A WIDE RANGE OF DIRECTIONS
TYPES OF ANIMAL
PREDATORS PREY
EXAMPLE OF ANIMALS
TIGERS,WOLVES,OWLS
DERRS,CHICKENS.RABBITS
OP TI CAL INT RU ME NTS
Microscope
To see object that are too small for the naked eye.
OPTICAL INTRUMENTS USED TO OVERCOME THE
LIMITATION OF SIGHT
Invented in 1625 by Zacharias Janssen in Netherlands.Optical microscope (the first invented), have one/more lenses that are refractive glass and occasionally of plastic to focus light into the or another light detector.
Telescope
To see far-off objects such as stars and planets.
Ivented in 1605 by Hans Lippershey.The first known practical telescope were invented in Netherlands.An instruments that aids in the observation of remote objects by collecting electromagnetic radiation.
Binoculars
To see tiny distant objects such as birds in the sky.Invented in 1825 by J.P Lemiere.A pair of identical or mirror-symmetrical telescope mounted side by side aligned to point accurately in the same direction allowing the viewer to use both eyes when viewing distant object.
MAGNIFYING GLASS
To make tiny objects appear larger than the original.Invented in 1250 by Roger Bacon.Convex lens that is used to produce a magnified image of an object.Also called a hand lens in a laboratory contexts.
Ultrasound machine
To scan and see the foetus in a pregnant mother.Invented in 1957 by DR. Lan Donald.A cyclic sound pressure wave with frequency greather than the upper limit of the human hearing range.
Periscope
To see a view beyond and obstracting object.Invented in 1450 by Johannes Gutenberg.An instrument foe observation from a concealed position.Consist of an outer case with mirrors at each other at 45 degree angle.
X-ray machine
To see the internal organs or to inspect baggages at the airports.Invented in 1895 by Wilhelm Conrad Rontgen.
Sight is very important for human being and animal to
ensure their survival.With
sight,human being and animals can
differentiate danger from other animals
and enemies from the face reaction or
action.
DEVICES USED TO OVERCOME THE LIMITATIONS OF HEARING
Understanding sound
Li mi tat ion of hea ri ng
A person with normal senses of hearing can only detect sounds between 20 Hz and20 000 Hz (hertz).
Different people have different ranges of hearing.As we grow older,our range of hearing decreases.
There is also the limit to how far our ear is able to hear sounds from a distance.
We also cannot hear very soft sound like our heartbeat.
The limitations of hearing can be overcome by using hearing aids.
Hea ri ng de vi ces
Helps doctors to detect soft heartbeat of patients.Invented in 1816 by Rene Laennes at the Necker-Enfants Malades Hospital in Paris,France.It is an acoustic medical for auscultation or listening to internal sounds of an animal or human body.
Mega phone
Used to amplify a person’s voice or other sound and direct it in a given direction.Invented in 1655 by Samuel Morland and Athanasius Kircher.Boosts a weak sounds and increases the volume of the sound.
Ear phone
Collects and amplifies sounds before sending them to the middle ear.Invented in 1910 by Nathaniel Baldwin in Stratford, Ontario ,Canada.They provide hardly any acoustic isolation and leave room for ambient noise to seep in user may turn up the volume dangerously high to compensate,at the risk of causing
hearing loss.
Public address
system
Amplified voices so that they can be heared from far away.Invented by Edwin Jensen and Peter Pridham.
The term is also used for systems which may additionally have a mixing consale and amplifiers and loudspeakers.
HEARING AIDS
Attached to the ears ( Open-Ear-Fitting/OEF )
Hearing aids are small and thin wires connected to the receiver ( receiver) that directs sound into the ear .
- Comfortable and small
- Sound is more natural and less clogging
- Appearance of stylish and colorful
- Suitable for mild hearing impairment and moderate
Behind the ear ( Behind -The- Ear / BTE )
This hearing curved and placed behind each ear. The sound delivered through a tube into the ear canal .
- High amplification to help problem hearing mild to very severe levels
- Size larger and easier to use , especially for those who have difficulty handling small objects
- The battery life is much longer
In Ear / In ear canal ( In-The- Ear (ITE ) / In-The- Canal (ITC )
Made with a special ear mold and fitted comfortably in the outer ear or ear canal
- The sound directly into the ear for ensure optimum performance
- Safe and comfortable in the outer ear
- Suitable for moderate hearing to severe levels
Hearimg ensure human being can
enjoy difference type of sounds such as wind blowing,bird
singing,wolf howling,dog barking
and ect.