Sound grade 7
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Sound is a mechanical wave that requires a medium to travel. It is produced when an object vibrates, exerting a force on the surrounding air or medium. The loudness of a sound is measured in decibels, with louder sounds having higher amplitudes. Sound travels fastest through materials with high density, as the closer molecules can transfer energy more quickly through collisions. The human ear can detect sounds from 20-20,000 Hz but some animals can hear ultrasonic or infrasonic waves outside this range.
Sound grade 7
- 1. SOUND KRIS ANN MAE YAP- BONILLA GRADE 7 SCIENCE SUBIC NATIONAL HIGH SCHOOL
- 2. Sound is a mechanical wave (requires a medium to travel) and a compressional/ longitudinal wave (molecules colliding).
- 4. Compressions The close together part of the wave Rarefactions The spread-out parts of a wave
- 7. Waves transfer energy without transferring matter.
- 9. In which media does sound travel fastest? Sound travels better through high-density materials The closer the molecules are together, the faster they can collide and transfer energy
- 10. Hearing and the Human Ear
- 14. Pitch -description of how high or low the sound seems to a person Loudness how loud or soft a sound is perceived to be.
- 15. Loudness of Sound in Decibels Sound Loudness (dbs) Hearing Damage Average Home 40-50 Loud Music 90-100 After long exposure Rock Concert 115-120 Progressive Jet Engine 120-170 Pain
- 16. KINDS OF SOUND WAVES 1. AUDIBLE SOUND - human ear can hear ( 20 – 200 000 Hz) 2. ULTRASONIC WAVES above 20 000 Hz - Cannot be detected by human ear but some animals do. - Dogs can detect as high as 50 000 Hz and bats can hear up to 100 000 Hz. - Uses in ULTRASOUND
- 18. - Sound below 20 Hz. SOURCES OF INFRASOUND: - Vibrating heavy machines - Earthquakes - Thunder - Volcanoes - It cannot be heard by human ear but can cause damage. 3. INFRASOUND WAVES
- 19. The range of hearing, singing, and the quality of notes.
- 24. Sound is produced when an object vibrates. When an object vibrates it exerts a force on the surrounding air Loudness of a sound is recorded in decibels As a sound gets louder, the amplitude of the wave increases.
- 25. The moving air mass carries the sound of the vibration to your ear. The air is the MEDIA that it travels through. Medium is what the wave travels through (ex. solid, liquid, gas) NO MEDIUM NO SOUND!!!!
- 26. Self Check!