Science Exam Study Guide
I. Properties of waves and sound.
a. Know and be able to describe the following:
Wave: A disturbance that transfers energy from place to place Transverse wave: A wave that moves the medium in a direction perpendicular to the direction in which the wave travels. λ (wavelength): The distance between two corresponding parts of a wave. Compressional/longitudinal wave: A wave that moves a medium in a direction parallel to the direction in which the wave travels. Intensity: The amount of energy per second carried through a unit area by a wave Loudness: Perception of the energy of a sound
Amplitude: The max distance the particles of a medium move from their rest positions as a wave passes through the medium. (Distance from crest or trough to rest position) Medium: The material through which a wave travels.
Crest: The highest part of a transverse wave.
Trough: The lowest part of a transverse wave.
Rarefaction: The part of a longitudinal wave where the particles of the medium are far apart. Compression: The part of a longitudinal wave where particles of the medium are close together. Infrasonic: Sound waves with frequencies below 20 Hz (human audibility). Ultrasonic: Sound waves with frequencies above 20,000 Hz (human audibility). Frequency: The # of complete waves that pass a given point in a certain amount of time Pitch: Perception of the frequency of a sound.
Doppler Effect: The change in frequency of a wave as its source moves in relation to an observer. Pitch of a moving sound is higher when closer; crests are closer together. Velocity: The speed of something in a given direction.
Speed of sound: At 20 degrees Celsius, about 343 m/s. Direct variation between elasticity and sound/ temp. and sound. Inverse variation between density and sound. Wave interference: The interaction between waves that meet. Constructive: When waves combine to make a wave with a larger amplitude Destructive: When waves combine to make a wave with a smaller amplitude Resonance: The increase in the amplitude of a vibration that occurs when external vibrations match an object’s natural frequency. Closed-end air column: Consists of a tube with one end closed off. Refer to packet. b. Transverse Wave: Draw a transverse wave diagram when given amplitude, wavelength. II. The Electromagnetic Spectrum http://www.darvill.clara.net/emag/index.htm a. List the 7 types of electromagnetic radiation in order from longest to shortest wavelength. Relationship between frequency and wavelength of an EM wave? Radio wave, Microwave, Infrared, Visible light, Ultraviolet, Soft X-Rays, Hard X-Rays, Gamma Rays The higher the frequen...