Study Guide for Exam #1

 

This looks like a lot of information and it is, but remember that a lot of these concepts are very interrelated! Good luck!

 

There will not be specific questions or problems on the laws of exponents or the laws of logs – however, these make working the decibel problems much easier so make sure that you review them enough to be able to use them in the decibel problems.

 

For the following concepts, make sure that you know (not all of these apply to everything listed below): the definition, the units associated, the abbreviation if given (makes using the formulas much easier), how to use the formula (remember that formulas will be supplied – see the next section of the study guide), if it is a scalar or vector quantity:

 

Time

Mass

Weight

Density

Length

Elasticity

Newton’s First Law of Motion: Inertia

Newton’s Third Law of Motion: Reaction Forces

Displacement

Velocity

Speed

Acceleration

Force

Newton’s Second Law of Motion

Pressure

Equilibrium

Hooke’s Law

Spring constant

Stiffness

Compliance

Momentum

Law of Conservation of Energy

Energy

Work

Power

Intensity

Potential energy

Kinetic energy

Friction

Sound

Sound source

Propagation medium

Brownian motion

Receiver

Condensation

Compression

Rarefaction

Speed of sound

Waveform

Sine wave

Sinusoids

Fourier series

Fourier’s Theorem

Frequency

Period

Wavelength

Amplitude

Instantaneous amplitude

Peak amplitude

Average amplitude

Root-Mean-Square amplitude

Starting phase

Decibel

Interval scale

Ratio scale

Log scale

Intensity level

Sound pressure level

dB IL

dB SPL

Reference intensity (remember you need to know both values)

Reference pressure (remember you need to know 2x10 –5 N/m2  and 2x10 –4 dynes/cm2)

0 dB IL

0 dB SPL

Inverse Square Law

Complex Stimuli

Periodic waveforms

Aperiodic waveforms

Line spectrum

Continuous spectrum

Fundamental period

Bandwidth

Noise

Transients

Speech (which sounds have periodicity and which do not?)

Filters

Cutoff frequency

High-pass filter

Low-pass filter

Band-pass filter

Band-reject filter

Gain

 

 

 

Formulas (these will be supplied but make sure that you know how/when to use them; they will not be labeled-when studying, try to fill in what each one is in the space to the right):

 

                           (x2 - x1)

               v  =      ---------

                           (t2 - t1)

 

 

 

 

                     (v2 - v1)

               a  =      ---------

                           (t2 - t1)

 

 

 

 

               F  =  ma    

 

 

 

 

 

                       F

               P  =      ---   

                            A

 

 

 

 

 

               Fr =  - k x

 

 

 

 

 

               Fm = mv

 

 

 

 

 

               w = Fx

 

                      w

               P =    ---

                          t

 

 

 

 

             P

               I =  ---

                      A

 

 

 

 

 

               Ff = Rv

 

 

 

 

               1

               T  =    ---

                           f

              

 

 

                 c

                l  =      ---

                              f

 

 

 

 

               ARMS = 0.707 x APEAK

 

 

 

 

                                                Ix

               dB IL =         10  log10   ----

                                               Iref

 

 

 

                                                Px

                    dB  SPL =         20  log10   ---- 

                                               Pref

 

 

For the following, be able to briefly describe:

 

The movement of a spring-mass system

The movement of a tuning fork

The relationship between frequency and period

The relationship between frequency and wavelength

The requirements for a sound transmission system

Five possible outcomes in a sound transmission system

Types of sound fields

The relationship between intensity and pressure

The relationship between intensity and distance to a sound source

The relationship between pressure and distance to a sound source

The relationship between dB IL and dB SPL

The relationship between bandwidth and duration

The differences between filter types (e.g. high-pass vs. low-pass; band-pass vs. band-

reject)

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