Sound and Light
concave lens
A lens that is thicker at the edges than at the middle is a ____________________ .
opaque
A material that does not allow any light to pass through is ________________ .
pitch
A sound with a high frequency has a high ____________ .
reflect
Apples __________ light.
light bulb
Are the lights in a stadium more like a laser or like a light bulb?
opaque
Books, chairs, walls and floors are ____________________ .
yes, one example is an echo
Can sound reflect?
no
Does a light bulb have as much energy as sunlight?
Sound travels faster through the ground than through the water. Since the water is underground, elephants can sense the vibrations made by movements of the water.
Elephants can detect sources of underground water by using their feet. Use what you know about sound waves to explain how this is possible.
There is no matter to serve as a medium, so you can't hear anything.
Explain what happens to sound in space.
refract
Eye glasses, contact lenses, rectangular prisms, a circular jar, and water all bend, or _____________, light.
steel
Factories use laser light to cut _________________ .
tuba
Four instruments: french horn, tuba, trombone, trumpet. Which one makes sounds with the lowest frequencies?
transparent
Glass, water, and plastic wrap are __________________________ .
mediums
Ground, water and air are examples of ____________________ .
1. Intensity of volume (softness or loudness) ; 2. Frequency of pitch (low or high)
How do we describe sound?
It absorbs the sound.
How does insulation keep a room in a house quiet?
The light reflects.
How does light behave when it encounters a mirror?
The light is absorbed into it.
How does light behave when it encounters a tree?
The light travels through.
How does light behave when it encounters plastic wrap?
The light bends, or refracts.
How does light behave when it encounters water?
It travels in transverse waves, like water waves. It does not compress matter as it travels.
How does light travel?
Sound travels through mediums by vibrating.
How does sound reach your ear?
about 8 minutes
If the sun suddenly stopped shining, how long would it be before we knew it on Earth?
light
If you are watching an explosion that occurs in space, would you observe light or sound?
It can be reflected, refracted or absorbed.
In what three ways can direction of the light changed?
translucent
Is a stained-glass window transparent, translucent, or opaque?
Light waves can travel through empty space, but sound waves cannot.
Light and sound are both forms of wave energy. How are light and sound different?
energy
Light and sound are forms of _________________ .
predictable
Light and sound behave in _____________________ ways.
emit
Light bulbs ____________ light.
light bulb
Light from what source spreads out in all directions as it gets farther from the source?
convex lens (The persons eye would be on the right for both of these pictures.)
Light rays are bent and brought together by a _______________ .
interacts
Light travels and maintains its direction until it ______________ with an object.
medium (In this picture the light has traveled from the air to the water.)
Light travels and maintains its direction until it moves from one _______________ to another.
thousands
Light waves move _____________________ of times faster than sound waves.
absorb
Opaque objects __________________ some light and reflect the rest.
Shakira would see the lightning first because the light travels faster than sound.
Q #1: Shakira is watching an approaching thunderstorm from her house. She can see and hear the lightning and thunder in the distance. Would Shakira see the lightning first or hear the thunder first? Explain.
The time difference between seeing the lightning and hearing the thunder will get smaller as the distance between the thunderstorm and Shakira's house decreases.
Q #2: Shakira is watching an approaching thunderstorm from her house. She can see and hear the lightning and thunder in the distance. How will Shakira's observations of the lightning and thunder change as the thunderstorm gets closer?
reflect
Smooth surfaces _______________ a lot of light.
vibrating
Sound is produced by _________________________ objects.
medium
Sound requires a _______________________ , such as ground, water, or air, through which to travel.
pitch
Sound: rate of vibration is related to the _______________ of the sound.
string length
Stephen is making sound waves by using strings of 12 different lengths. Identify the variable in Stephen's experiment.
refraction
The bending of light as it moves from one material to another is ________________ .
decreases
The energy you get from a light bulb __________ as you move away.
volume
The loudness of a sound is also known as _____________________ .
reflects
The moon ________________ light.
emits
The sun ___________ light.
light
This can be reflected, refracted or absorbed.
bend
Transparent objects let light pass through, although they make the light _________, or refract.
transparent
Water and plastic wrap are materials that are ______________________ .
translucent
Wax paper and bubble paper are ______________ .
translucent
Wax paper is ___________________________ .
They are soft materials with air pockets in them.
What are the characteristics of objects that absorb sound?
It can travel through a solid, liquid, or gas.
What can sound travel through?
light
What can travel through space; light or sound?
Something causes a vibration that travels through matter that eventually reaches our ears.
What causes sound?
They carry energy.
What do all waves have in common?
They need a medium, such as ground, water or air.
What do sound waves need for the waves to travel?
It spreads light apart.
What does a concave lense do to light?
It makes food hot.
What does the energy from microwaves do?
laser
What gives off light in a narrow beam?
almost all the light waves bounce back
What happens when light waves hit a mirror?
It is a range of wave energies with different frequencies. it includes visible light, infrared, x-rays, microwaves, ultraviolet and radio waves.
What is the electromagnetic spectrum?
The number of decibels increases.
What is the result of someone hitting a drum harder than before?
convex lens, it can be used as a magnifier, and also in your glasses
What kind of lens is thicker at the center and it bends light waves to make them come together? It makes objects look bigger.
concave lens, it can be used in the viewfinder of a camera, it shrinks things
What kind of lens is thicker at the edges? It spreads light waves apart to make objects look smaller?
laser
What kind of light might damage a person's eyes?
The letter S, stretched out and sideways. The wave vibrates up and down in the same way as a rope when you hold one end and shake it.
What letter of the alphabet best describes the shape of a transverse wave, or light wave? Why?
matter must vibrate
What must happen in order for a sound wave to form?
nothing
What travels faster than sunlight?
light
What travels faster, light or sound?
convex
What type of lens can be found in a microscope?
reflection
When light bounces off a surface it is called ___________________ .
refraction
When light moves into a different material, it bends. This bending of light is called _______________________ .
light that has not been absorbed
When we see a colored object, what are we really seeing?
x-rays; they have a higher frequency and have more energy
Which has more energy, microwaves or x-rays? Explain your answer.
ultraviolet waves
Which kind of wave can damage your skin?
infrared waves
Which kind of waves can be used as heat?
radio waves
Which kind of waves can carry signals to wireless devices, such as cell phones and computers?
sunlight
Which one will give you a sunburn, light bulbs or sunlight?
They absorb the sound so the people living in the houses nearby have peace and quiet.
Why do construction workers build walls next to highways?
This kind of energy can be spread out more--this means that if you are closer, more energy hits your ear. Also the density of the medium determines how fast the sound moves.
Why do some sounds travel farther than others?
The stars are very far away. The light from the stars spreads out in all directions and only a tiny bit of it reaches Earth.
Why do the stars look like small pinpoints of light instead of bright, giant disks?
Light travels faster because it does not need to pass energy from one particle of matter to another. Light waves also have more energy than sound waves.
Why does light travel so much faster than sound?
It travels as a wave through materials. The individual parts of the materials vibrate, causing their neighbors to vibrate. These neighbors affect their neighbors further out, etc. In some materials the particles are closer together than in other materials. The material itself does not travel from one end to the other, but rather the disturbance, or energy travels.
Why does sound travel through some objects better than others?
It is absorbed.
Why don't you hear much sound when you drop a spoon on the carpet?
absorbs
You feel the energy in light when you stand in sunlight. Your body _______________ the energy, and you feel it as heat.
White
_____________ light is the combination of all colors of light.