Unit IV - Wave Phenomena I. Introduction to Waves Wave – __________________disturbance that travels through a material or space Ex) ____________________________________ A. Waves and Energy 1. Waves ___________ ___________________from one place to another with no transfer of ____________ 2. Waves can be produced in two ways: a. Vibration of _____________________(requires a ___________________ ex) _______________________________________________ b. Small _______________ in the strength of an _____________ (requires ______________________________) ex) _______________________________________________ B. Pulses & Periodic Waves
1. Pulse – _____________________vibratory disturbance that moves from point to point
a. When the pulse reaches a boundary with another medium, part is ______________ and part is _______________ b. When a pulse reaches a _____________, unyielding boundary, then the pulse is completely ________________________________________ 2. Periodic Wave – series of ________________________ disturbances in a medium
pulse periodic wave C. Vibrations and Waves
1. Longitudinal – a vibrational disturbance which is _________________to the direction in
which the wave travels
ex) ______________(think of a guitar string) 2. Transverse – vibrational disturbance which ________________________ to the direction in which the wave travels ** Unlike longitudinal, transverse waves can be _______________ in many different
planes.
Ex) ______________________________________________________ II. Characteristics of Periodic Waves A. Frequency - f = ____________________ Units ( ) Frequency is determined by ______________________________________ How many cycles are shown from dot to dot? ________ (one single vibration) Ex) 10 cycles pass a fixed point in a wave train in 5 seconds.
What is the frequency of the wave?
Ex) A wave generator operating for 4 seconds produces the waves drawn above.
What is the frequency of this periodic wave train?
How many waves are drawn? _______ (Be careful!!)
f = __________
· In Sound, frequency determines ________________. · In Light, frequency determines _____________________. The human ear can detect a frequency between_________________________
B. Period – ___________________________________given point in a medium C. Amplitude – _____________________________________ during a single vibration
determined by ___________________________ Ex) Compare waves A & B
1. _______________ of a wave shows the amount of __________ in the wave a. Amplitude is a measure of __________________
D. Phase "In Phase" – points on a single periodic wave that has the _________________________ from the equilibrium position, and moving in the ___________________ _______________ number of wavelengths apart A & ____ A & ____ A & ___ B & ___ B & ___ Out of Phase "– (________) _________ displacement from equilibrium position but going in a ___________direction |