Light And Sound Flashcards
Pitch
How high or low a sound is
Hertz
How pitch is measured 1 wave/1 second
Infrasound
Sound below 20 Hertz
Ultrasound
Sound above 20,000 Hertz
Intensity
The amount of energy in sound, the higher the intensity, the higher the amplitude
Decibel
The unit used to measure volume
Doppler Effect
The perceived change in pitch as a object creating a sound is moved past a listener
Sound quality
The quality of every object producing its own sound
Transmission
The movement of waves through matter
Reflection
The bouncing back of a wave after hitter an object
Absortion
The disappearing of a wave into an object
Transparent
Almost all light passes through
Translucent
Some light passes through
Opaque
Not light passes through
Scattering
The spreading out of a wave because particles are either reflecting or absorbing the light
Primary Colors
The colors that combine to make any other colors
Secondary Colors
The colors produced when two primary colors are combined equally
Complementary Colors
Any two colors that combine to produce white light or black pigment
Concave Mirror
A mirror that reflects light inwards making the object appear upside down
Convex Mirrors
A mirror that reflects light outwards and has no focal point
Concave Lens
Lens is reflected outward twice. This causes the image to be both smaller and upright.
Convex Lens
Light is refracted inward twice once when entering the lens and again when exiting the lens. This makes the image appear right side up and upside down.
Focal Point
Where all reflected light rays cross each other
Cones
Cells that respond to color, specifically the prime colors of light, red, green and blue.
Rods
Cells that resound to movement and contrast
Regular Reflection
Reflection off a flat surface. Parallel light rays remain parallel.
Diffuse Reflection
Reflection off an irregular surface. Parallel light rays reflect in different directions.
Factors that affect the speed of sound
- Temperature: The higher the temperature the faster the speed of sound
- Stiffness: The stiffer the material the faster the speed of sound
- Density: Typically the denser the material the faster the sound. But stiffness plays a role. 2 materials of equal stiffness but different densities will transfer differently. The denser will be slower.
What is the relationship between pitch and frequency?
Frequency determines pitch. The higher the frequency the higher the pitch.
What is the range of human hearing? What is the range of infrasound and ultrasound?
Human hearing: 20 Hz to 20,000 Hz
Infrasound: Sounds below 20 Hz
Ultrasound: Sounds above 20,000 Hz
Why do sounds fade?
When waves spread out so their is less energy
Define the Doppler effect and explain it
The perceived change in pitch when an object making a sound moves past the listener. When it pulls past the waves begin to get farther and farther apart causing the waves to spread out, so the pitch would drop.
Why do instruments sound different?
Sound quality
Fundamental Tones
The actual note/tone being played
Overtones
High frequency waves produced by the object
What is the electromagnetic spectrum from low frequency to high?
Radiowaves Microwaves Infared Ultraviolet Visible X-rays Gamma rays
Primary and secondary colors of pigment?
Primary: Yellow, Magenta, Cyan
Secondary: Green, Red, Blue
Primary and secondary colors of light?
Primary: Red, Green, Blue
Secondary: Yellow, Magenta, Cyan
What type of lens is in our eye and how does it work?
Convex
How are images formed through convex lens?
Light is refracted inward twice once when entering the lens and again when exiting the lens. This makes the image appear right side up and upside down.
How are images formed through concave lens?
Light is reflected outward twice. This causes the image to be both smaller and upright.
