Exam 1

Question 1

Sound

Answer 1

the vibrations of a sound source, transmitted through the air or another medium, that have the potential to stimulate the organs of hearing

Question 2

Elasticity

Answer 2

the restoring force that causes an elastic medium to bounce back when stretched or displaced

Question 3

Inertia

Answer 3

the tendency for motion or lack of motion to continue

Question 4

Compression

Answer 4

molecules are closer together and the air pressure is tighter

Question 5

Rarefaction

Answer 5

Molecules are farther apart and air pressure is lower

Question 6

Sinusoidal motion or simple harmonic motion

Answer 6

moving back and forth a fixed number of times per second no matter how hard the tuning fork is struck

Question 7

Amplitude

Answer 7

intensity or power of the sound

Question 8

Wavelength

Answer 8

distance from any point in one cycle to the corresponding point in a neighboring cycle

Question 9

Cycle

Answer 9

one cycle of vibration is completed at the point where the motion of a vibrating body or a pressure wave begins to repeat itself

Question 10

Period

Answer 10

the time taken for each cycle of vibration

Question 11

Frequency

Answer 11

the number of completed cycles (back-and-forth movements) per second; expressed in units of Hertz

Question 12

Complex sound

Answer 12

sound having more than one sine wave component

Question 13

Spectrum

Answer 13

an indication of the frequency and amplitude of each harmonic in a complex periodic wave

Question 14

Periodicity

Answer 14

the pattern of vibration, however complex, repeats itself exactly over time

Question 15

Aperiodicity

Answer 15

vibration is random and displays no repeatable pattern

Question 16

Power/intensity

Answer 16

Magnitude of sound expressed in power or pressure; dB IL = 10(log10 Wo/Wr)

Question 17

Pressure/SPL

Answer 17

force per unit area; dB SPL = 20 (log10 Po/Pr)

Question 18

Resonance

Answer 18

vibratory response to an applied force

Question 19

Natural Resonant Frequency

Answer 19

frequency in which the swing completes a cycle during 1 second

Question 20

frequency from period (formula)

Answer 20

F =1/p

Question 21

Period from frequency (formula)

Answer 21

P = 1/f

Question 22

Wavelength from Period (formula)

Answer 22

fλ = c; c = 344 m/s; λ = c/f = 344(m/s)/200 Hz = 1.72 m

Question 23

dB SPL

Answer 23

dB SPL = 20(log10 Po/Pr)