WELCOME

INTRODUCTIONNAME – RUDRADATTSINH GOHIL

ROLL NO - 06

STD – 8TH

SUBJECT – SCIENCE

SUB-TEACHER – VINAY PANDYA SIR

DEFINE OF SOUND

Sound is a mechanical wave of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong

1) It is a sequence of waves of pressure that propagates through media such as air or water.

2) The perception of sound in any organism is limited to a certain range of frequencies. For humans, hearing is normally limited to frequencies between about 20 Hz and 20,000 Hz (20 kHz)

4) IT IS TRANSMITTED THROUGH GASES, AIR AND LIQUIDS AS LONGITUDINAL WAVES, ALSO CALLED COMPRESSION WAVES.

3) The speed of sound depends on the medium the waves pass through, and is a fundamental property of the material.

5) Sound waves hit the ears at different times causing the brain to focus on the cause of the wave.6) The speed of sound depends on the elasticity and density of the medium through which it is traveling.

7) sound waves are reflected, refracted, and diffracted, and exhibit interference8) A vibrating object will produce sound waves in the air. For example, when the head of a drum is hit with a mallet, the drumhead vibrates.

9) Sounds of a single pure frequency are produced only by tuning forks and electronic devices called oscillators

10) IT IS PRODUCED BY THE VIBRATIONS IN A VIBRATING MATERIAL BODY.

11) Sonar is the device used in ships for determining the depth of the sea below the ship12) It travels fastest in solids (its speed is about 5000 m/s in steel and glass), slower in liquids (its speed is about 1300-1600 m/s in water) and slowest in gases (its speed is 330 m/s in air).

THANK YOU

Sources-

1) http://en.wikipedia.org/wiki/Sound

2) www.physicsclassroom.com/class/sound/soundtoc.html

3) http://scienceworld.wolfram.com/physics/Sound.html

4) TEXTBOOK OF CBSCE 8TH CLASS ON PAGE NUMBER 164 1ST PARAGRAPH

5) http://science.howstuffworks.com/search.php?terms=sound

6) http://www.syvum.com/cgi/online/serve.cgi/squizzes/physics/sound.html