ഭൗതികശാസ്ത്രത്തിലേക്ക് തിരികെ വരുമ്പോൾ ശബ്ദവുമായി ബന്ധപ്പെട്ട ചോദ്യങ്ങളാണ് ഇന്നത്തെ പാഠത്തിൽ.
- Study of Sound
Acoustics
- Sound waves cant travel through
Vacuum
- Sound waves are
Longitudinal
- Sound travels faster in
Solids
- Sound travels slower in
Gases
- Solid medium in which speed of Sound is maximum
Steel
- Hearing capacity of human
20 to 20,000 Hz
- Speed of Sound in air
340 m\s
- Speed of Sound in water
1453 m\s
- As the density of medium increases, speed of Sound
Increases
- As the temperature of medium increases, speed of Sound
Increases
- Properties of Sound
Pitch, Loudness, Timbre (Quality)
- Shrillness of Sound is known as
Pitch
- Intensity of Sound is identified as
Loudness
- Unit of frequency of Sound
Hertz (Hz)
- Unit of Intensity of Sound
Decibel (db)
- Unit of Sound Pollution
Decibel
- Normal unit of measuring Pollution
Parts per million (ppm)
- Normal Sound level
60-120 db
- Intensity of human sound
60-65 db
- Sound level causing damage to human ears
Above120 db
- Sound allowed in hospital areas at night
About 40 db
- Sound allowed in residential areas
50 db in day 40 db at night
- Organ in human beings which helps to produce Sound
Larynx
- Sound is produced due to
Vibration
- Phenomenon of sound to obstructed by a hard surface and send back to source is called
Reflection of Sound
- Echo and Reverberation are due to
Reflection of sound
- A vibrating system or external force drives another system to oscilate with greater amplitude at a specific freaquency is known as
Resonance
- Persistence of sound as a result of multiple reflection is known as
Reverberation
- Phenomenon of hearing a sound reflection after hearing the original sound is
Echo
- Minimum sound required for the production of Echo
17 Meter
- Phenomenon of sound which used in Stethoscope
Reflection of sound
- Phenomenon of sound which used in SONAR
Echolocation
- Sound waves used in SONAR
Ultrasonic Sound
- SONAR stands for
Echolocation
- Devices used to measure the depth of the sea
Echo Sounder (SONAR), Fathometer
- Unit of measuring the depth of the sea
Fathom (1 Fathom= 6 Feet=1.82 metre)
- Devices used to get the picture of the objects at the bottom of the sea
SONAR
- Whistle used for calling dogs
Galton whistle
- Devices used in the studies of sound
Sonometer
- Device used for recording sound under water
Hydrophone
- Term used to denote the speed lower than the speed of sound
Subsonic
- Term used to denote 2 times the speed of sound
Supersonic
- Term used to denote 5 times the speed of sound
Hypersonic
- Sound waves produced by Elephants and Whales for communication
Infrasonic
- Sound waves produced by Bats and Dolphin
Ultrasonic
- Sound waves used in Ultrasound scanning
Ultrasonic
- Sound lower than 20 Hz
Infrasonic
- Sound higher than 20,000 Hz
Ultrasonic
(To be Continued…)