What puts the BOOM in fireworks? Chapter 4 Lesson one: What is
Sound Energy?
Slide 3
Fireworks are seen before they are heard because the speed of
light is much faster than the speed of sound. While the speed of
light is 300,000,000 meters per second, the speed of sound in dry
air is only about 343 meters per second. So, if fireworks explode
1,000 meters away, it will only take three millionths of a second
for the light to reach the viewer. However, the loud boom will take
about three seconds. When fireworks explode, chemical energy is
released quickly as light energy, sound energy, and heat. The quick
release of energy into the air around the explosion makes the
surrounding air expand faster than the speed of sound. This
produces a shock wave of sound energy you hear as the BOOM.
Fireworks are seen before they are heard because the speed of light
is much faster than the speed of sound. While the speed of light is
300,000,000 meters per second, the speed of sound in dry air is
only about 343 meters per second. So, if fireworks explode 1,000
meters away, it will only take three millionths of a second for the
light to reach the viewer. However, the loud boom will take about
three seconds. When fireworks explode, chemical energy is released
quickly as light energy, sound energy, and heat. The quick release
of energy into the air around the explosion makes the surrounding
air expand faster than the speed of sound. This produces a shock
wave of sound energy you hear as the BOOM.
Slide 4
What is Sound? It is energy in the form of vibrations passing
through matter. A quick vibration is a quick back-and-forth
movement.
Slide 5
How does sound travel? As sound waves travel through matter,
they set particles into motion The moving particles form a pattern
Groups of particles that a bunched together alternate with
particles that are further apart The area were particles are
bunched together are called compressions.
Slide 6
Think Questions? How does a sound wave move through matter? How
is a ball dropping to the floor and bouncing back like an echo?
When vibrations from an object slow down, how are wavelength and
frequency affected?
Slide 7
Answers! 1. A sound wave compresses the particles in matter.
Then the particles bounce back to their original position. 2. A
ball bounces back up from the floor. Sound that bounces back, or
reflects, from a hard surface is an echo. 3. Wavelength becomes
longer, and frequency becomes lower.
Slide 8
Frequency The frequency of a wave is the number of waves that
pass a point in a certain amount of time.
Slide 9
Wavelength Is the distance between a point on one wave and a
similar point on the next wave
Slide 10
Pitch, Volume, and Amplitude Pitch is how high or low a sound
is. Volume is a measure of how strong a sound seems to us.
Amplitude is the height of a wave measured from its midline.
Slide 11
True or False? The higher is the amplitude of a wave, the
quieter it sounds? False- because the higher the amplitude of a
wave, the more energy it has, and the louder it sounds. Objects
that vibrate more quickly have fewer frequencies? False-because
objects that vibrate more quickly have higher frequencies.
Slide 12
THICK QUESTION How would a drum played on Earth sound different
from a drum played in outer space? A drum played on Earth would
create sound because there is air through vibrations can pass.
However, outer space is empty, so a drum played there would create
no sound.