1. Observations | Questions | Discussion| Key Concepts

2. Mara Cabrera
Dang David
Jovelle Delos Reyes
Zonasha Musa
Kristabelle Ocampo
Chinina Perez
Ana Reyes
Armida Reyes
Agatha Sayurin

4.  Distance affects frequency
 Sound waves travel faster in solid
 Patterns are formed from the sounds made
 Solid is a better resonator than liquid
 The longer the tuning fork is, the lower the tone it
produces
 Chirping of birds and buzzing of bees differ from
volume/tone but they have alike patterns

6.  How is sound formed?
 How do we perceive sound?
 How does sound travels?
 Does the frequency of sound
decrease over distance?
 Why does sound has a higher
frequency in solid than in liquid?
 Does the universe resonate sound
waves?

8. How is sound formed?
• Sound waves are produced by vibrations of an object
• Vibration – to and fro motion of an object.
•Source of sound is always a vibrating body.

9. Sound is transmitted through material media in
pressure waves made up of alternate compression and
rarefactions.
Compression (forcing of Rarefactions (pulling of
the molecules of the the molecules of the
medium together) medium away from one
another).

10. How do we perceive sound?
We perceive sounds through our ears.
E A R - sound detector
-can detect sound waves over a wide range of
frequencies

11. • Sound waves that enter the ear cause the ear drums to
vibrate.
• These vibrations are passed on by three tiny ear bones
(hammer, anvil & stirrup)
• To the cochlea where they are detected by tiny hair
cells.
• These hair cells then send signals to the brain through
the auditory nerve, producing the sensation of sound.

12. How does sound travels?
1. Sound is transmitted by particles in a solid, liquid or gas
colliding with each other. It is a wave which is created by
vibrating objects.
2. Sound vibrations, then, travel outwards in all
directions in waves from a sound source. As they travel
outwards the energy they contain becomes dissipated and
therefore the sound becomes weaker the further it is from
the source.
3. Eventually the sound reaches the ear and is made into
signals which are sent to the brain.

13. Why does sound has a higher
frequency in solid than in liquid?
The molecules in soild are more tightly bound together
than that of solid

14. Hence, it is easier for sound waves to go through
solids than liquids.
From that we can say that the closer the molecules
are to each other and the tighter their bonds, the less
time it takes for them to pass the sound to each other
and the faster sound can travel.

15. Does the universe resonate sound
waves?
“The universe is not a silent movie. The universe
isn't silent. I'd like to convince you that the
universe has a soundtrack and that soundtrack is
played on itself because space can wobble like a
drum. It can ring out a recording of some of the
most dramatic events as they unfold.”
–Janna Levin

17. KEY CONCEPTS
 Without vibration, there is no sound.
 We perceive sound through our ears.
Sound travels through matter as a waveform.
The speed of sound depends on its
medium or resonator.
 Our universe creates sound too.
Sound is significant to our lives.

18. REFERENCES:
Padua, A. & Crisostomo, R (2010).
Science and Technology Series
Practical and Explorational Physics:
Modular Approach 2nd Edition
Quezon City: Vibal Publishing House, Inc.
http://www.tellmewhyfacts.com/2007/09/how-
does-sound-travel.html
http://www.huffingtonpost.com/2011/03/01/janna-
levin-at-ted-2011_n_829746.html
http://www.ndted.org/EducationResources/HighSc
hool/Sound/speedinmaterials.htm