Course:PHYS341/2018/Assignments/A1

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Training Problems for January 12th Quiz

Part 1

Basic Concepts. For questions 1 to 5, fill in the gaps in each paragraph, choosing from the set of words/phrases at the end of each question (each of which may be used more than once) to form the most correct, precise statements. In the case where two words can be interchanged with no change in meaning, place them in alphabetical order (the code cannot handle more than one correct answer!).

1

In colloquial use, the term "noise" refers to

sound. In science of acoustics, "noise" means

sound with no particular

or

content that tends to obscure the sound of interest.

amplitude, frequency, information, loud, random, quiet, unwanted.

2

"Music" means many things to different people, but basically it is

,

in a

meaningful way.

culturally, deliberately, harmonically, organized, pressure, sound, sung, technically, written.

3

"Vibration" means the regular back-and-forth movement of an object that can be defined by its

(i.e. the maximum

it moves from equilibrium) and

(the number of complete oscillations in a given

).

amplitude, buzz, distance, frequency, pressure, sound, time, wavelength.

4

Unless continually maintained with a source of energy, a vibration will

as it loses energy to the

, including sound. The

half-time is the time it takes to lose half its

for the strings of a string instrument, this time is of the order of a

.

amplitude, decay, distance, environment, frequency, minute, pressure, second, time, wavelength.

5

A standing wave occurs when two waves travelling in opposite directions

inside a cavity; as the name suggests, it doesn't go anywhere. The standing wave can only have certain

, determined by the

between the edges of the cavity.

amplitudes, decay, distance, environment, interact, medium, pressures, wavelengths.




Part 2

For the following questions, select all statements that are correct. There may be more than one.

1 A travelling wave permanently transports (i.e. not just a back and forth oscillation) what from one place to another?

(a) Air
(b) Atoms
(c) Energy
(d) Information

2 The "frequency" of a wave means:

(a) How often a sound happens
(b) The distance between two successive wave crests.
(c) The time between two successive wave crests.
(d) The number of wave crests that pass in a given time period.

3 The "wavelength" of a wave means:

(a) Where a sound happens
(b) The distance between two successive wave crests.
(c) The distance between two successive wave troughs.
(d) The number of wave crests that pass in a given time period.

4 The "amplitude" of a wave means:

(a) How far apart the waves are
(b) The distance between two successive wave crests.
(c) The maximum distance from the equilibrium (no wave) position.
(d) The number of wave crests that pass in a given time period.

5 For a wave, the wavelength multiplied by the frequency is:

(a) The wave speed
(b) The amplitude.
(c) The energy.
(d) The speed of the particles of the medium.

6 In a transverse wave:

(a) The particles of the medium travel at the wave speed.
(b) The particles of the medium oscillate in the wave direction.
(c) The particles of the medium oscillate at 90 degrees to the wave direction.
(d) The particles of the medium migrate in the direction of the wave