Communication Sciences Exam #1

Newton's 1st Law of motion

An object at rest or in motion will remain unless acted upon by an outside force

Newton's 2nd Law of Motion

Acceleration of an object is directly proportional to the net force acting upon it, and i inversely proportional to mass

-F=MxA

Newton's 3rd law of motion

For every action, there is an equal and opposite reaction

Brownian Motion

Random movement of particles in fluids such as a liquid or gas, resulting from collision with fast-moving atoms or particles.

-nature of sound waves

Velocity

Speed of something in a given direction

What is velocity measured in ?

m/s

Force

Strength or energy as an attribute of physical action or movement

Pressure

Force applied perpendicular to a surface per unit square area

What is pressure measured in?

Kpa and centimeters

Wave

disturbance traveling through medium, transferring energy from one point to another without transporting matter itself

Medium

A material substance that transmits energy from one point to another

Psychoacoustics

The study of the relationship between physical properties and our perception of those properties

Frequency

Cycle, one alternating compression and rarefaction, cycles per second, frequency is a measurement perceived as pitch by a listener

What is frequency measured in?

Hz

Period

Duration of one cycle

-Time measurement

What is period measured in?

seconds

-T(period in seconds= 1 sec/f

-T(period in milliseconds)= 1000/f

Brownian Motion

Random movement of particles in fluids such as a liquid or gas, resulting from collision with fast-moving atoms or particles.

-nature of sound waves

Velocity

Speed of something in a given direction

What is velocity measured in

m/s

Relationship between period and frequency

longer period--> lower frequency

Relationship between amplitude and intensity

amplitude doubles, intensity quadruples

Transverse Waves

Particle movement perpendicular

ex. fans in the stadium doing a wave

Longitudinal waves

Particle movement parallel

ex. slinkey

Pulse waves

Single disturbance

ex. clapping hands, /t/, /k/, African (Zulu/Chosa), click sound

Sinusoidal eaves

Simple harmonic motion, back/ forth motion repeats, periodic, the resulting sound is a pure tone, single frequency

Compression

Positive pressure

Rarefaction

Negative pressure

X-axis

time

Y-axis

Pressure

Inverse square law

-Intensity diminishes further away from the source

-Energy spreads out

Relationship: take the factor by which distance increases, intensit