waves science 8th grade Flashcards
_ waves REQUIRE a medium.
Mechanical
_ waves DO NOT REQUIRE a medium, but may use one.
Electromagnetic
_ Waves move parallel
Longitudinal
_ waves move perpendicular
Transverse
Frequency:
The number of wave cycles per second. Measured in Hz
Reflection of a wave:
the change of direction of propagation of a wave when it meets a boundary.
The angle of incidence:
The angle between the incident ray and a line normal to the surface at the point where the light strikes.
The angle of reflection:
The angle between the reflected ray and the normal ray
When sound waves are reflected, they create a
echoe
Refraction:
The bending as it passes through one medium to another
Interference:
When two or more waves meet at the same point in a medium and momentarily combine to form a single wave.
Constructive interference
Combined curves
deconstructive interference
forms full circle
What type of wave is a sound wave?
Mechanical
what type of wave is a light wave?
Electromagnetic
What two factors affect the speed of a wave?
The type of wave itself, and the medium
What is the doppler effect?
e increase (or decrease) in the frequency of sound, light, or other waves as the source and observer move towards (or away from) each other.
How is pitch related to wave length?
Pitch lasts as the wavelength widens
How is frequency related to wavelength?
Higher frequency, the shorter the wavelength
How is pitch related to frequency of a wave
The higher the frequency, the higher the pitch.
What does Amplitude measure?
The amount of energy carried by a sound wave
Reflection:
occurs when light traveling through one material bounces off a different material.
Refraction:
he change in the direction of a wave passing from one medium to another.
Diffraction:
Waves bend around a barrier or edges of an opening
Rarefaction:
A decrease in density and pressure in a medium, such as air, especially when caused by the passage of a wave, such as a sound wave.
Absorption:
a substance captures and transforms energy
Resonance
he occurrence of a vibrating object causing another object to vibrate a higher amplitude
Law of reflection:
when the light rays fall on the smooth surface, the angle of reflection is equal to the angle of incidence, also the incident ray, the reflected ray, and the normal to the surface all lie in the same plane.
What is an angle of incidence?
the angle between a ray incident on a surface and the line perpendicular (at 90 degree angle)
