Ch 22/23 Study Guide-Science Flashcards
Describe reflection and given an example.
The bouncing back of a ray of light, sound, or heat when the Ray hits a surface that it does not go through.
How does a sound wave work?
A sound wave is a longitudinal wave caused by vibrations and carried through a substance. The particles of the substance, such as air particles, vibrate back and forth along the path that the sound waves travel. Sound is transmitted through the vibrations and collisions of the particles.
What are reflected sound waves called?
Echo
What is happening when you hear an echo?
The sound waves are bouncing off of a surface.
What type of surface is best for reflecting sound waves?
Smooth, hard surfaces
What type of material should be used to reduce loud sounds and echoes?
Soft, absorbent materials
How does temperature affect the speed of sound? Explain.
The cooler the medium, the slower the speed of sound. There is more particle movement in warmer environments so sound waves can travel faster when the environment has a warmer temperature.
How does the state of matter affect the speed of sound? Explain.
Sound travels faster in solids than in liquids or gases. That’s because the particles are closer together so they don’t have to go as far to cause a chain reaction as they vibrate.
What is pitch?
Pitch is a measure of how high or low a sound is perceived to be depending on the frequency of the sound wave.
What determines pitch?
Frequency
What is it called when a sound has a frequency that is too high for humans to hear?
Ultrasonic
Describe refraction and give an example.
Refraction is the bending of a wave as the wave passes between two substances in which the speed of the wave differs. A rainbow is an example of refraction because the light waves change speed as they pass from the air to the droplets of water left in the air after it rains.
Describe diffraction and give an example.
Diffraction is a change in the direction of a wave when the wave finds an obstacle or an edge, such as an opening. You can hear music around a corner because sound waves have long wavelengths and ads able to diffract around corners.
Describe interference and give an example.
Interference is the combination of 2 or more waves that result in a single wave.
When does constructive interference occur?
When the crests of one wave overlaps the crests of another wave. The troughs of the waves also overlap.
What happens to the wave during constructive interference?
When this happens, the energy of the waves combine to form a new wave that has higher crests and troughs than the original wave.
When does destructive interference occur?
When the crests if one wave and the tonight’s of another wave overlap.
What happens to the wave during destructive interference?
The new wave has a smaller amplitude than the original wave had.
What is a sonic boom?
Th explosive sound heard when a shock wave reaches your ears. The result of constructive interference when a jet travels than the speed of sound. The result of sound waves combining by constructive interference to form shock waves.
Explain a standing wave.
A pattern of vibration that simulates a wave that is standing still.
A standing wave results from…..
A wave that is reflected between two fixes points. Interference form the wave and reflected waves causes certain points to remain at rest and certain points to remain at a large amplitude.
Sometimes when music is played loudly you can feel your body shake. Explain what is happening in terms of resonance.
Resonance is a phenomenon that occurs when two objects naturally vibrate at the same frequency. The sound produced by one object causes the other object to vibrate.
How does an oscilloscope helps someone see sounds?
An oscilloscope turns sounds into electrical signals and graphs the signals.
- Sound waves vibrate the eardrum- a lightly stretched membrane that is the entrance to the middle ear.
- The vibration of the eardrum makes the hammer vibrate, which in turn, makes the anvil and stirrup vibrate.
- The stirrup vibrates the oval window- the entrance to the inner ear.
- The vibrations of the oval window create waves in the liquid inside the cochlea.
- Movement of the liquid causes tiny hair cells inside the cochlea to bend.
- The bending of the hair cells stimulates nerves which send electrical signals to the brain.
How you hear.
What is the difference in music and noise?
Noise is a sound that consists of a random mix of frequencies.
What are the families of musical instruments?
String, percussion, woodwind, and brass instruments
