Mechanical Waves

Question 1

Types of Waves:

__________ - do not need any medium for propagation (light waves)
__________ - do not have electromagnetic properties
__________ - require a medium in order to propagate (sound waves, water waves)

Answer 1

Electromagnetic Waves
Matter Waves
Mechanical Waves

Question 2

Disturbance of a system from equilibrium that propagates from one region of the system to another

Types:
1. ______________ – Single, short-lived disturbance.
2. ______________ – Continuous, repetitive disturbance.

Answer 2

Wave

Impulsive Waves
Periodic Waves

Question 3

Mechanical Waves: Properties

• Disturbance travels with _________ speed.
• Medium does not travel through space, each particles _______ about their equilibrium points.
• Waves transport ______ but not ______ from one region to another.

Answer 3

definite
oscillate
energy but not matter

Question 4

Kinds of mechanical waves (2)

_________: Particles vibrate perpendicular to wave propagation.
_________: Particles vibrate parallel to wave propagation.

Answer 4

Transverse Waves
Longitudinal Waves

Question 5

Wave Characteristics

___________: Maximum displacement from equilibrium.
___________: Distance between two consecutive crests or troughs.
___________: Number of cycles per second (Hz).
___________: Time for one complete cycle (𝑇=1/𝑓).
___________: angular displacement per unit time
___________: Speed of wave propagation (𝑣=𝑓𝜆).

Answer 5

Amplitude
Wavelength (𝜆)
Frequency (𝑓)
Period (𝑇)
Angular frequency �
Wave Speed (𝑣)

Question 6

number of waves in a unit distance

Answer 6

Wave number k

Question 7

wave speed is dependent on the ______________ in which it travels.

Answer 7

properties of the medium

Question 8

Periodic wave with simple harmonic motion

Answer 8

Sinusoidal wave

Question 9

The ___________of a traveling pulse at the fixed end of a stretched string. The reflected pulse is ________, but its shape is otherwise unchanged

Answer 9

reflection
inverted

Question 10

The reflection of a traveling pulse at the _________ of a stretched string. The reflected is not inverted.

Answer 10

free end

Question 11

● The resulting effect when two or more waves overlap in the same region of space

Answer 11

wave interference

Question 12

When two or more waves overlap, the displacement at any point is the algebraic sum of the displacement of the corresponding points of the overlapping waves

Answer 12

The Principle of Superposition

Question 13

Results when the waves are in phase

Waves in phase add to form a larger wave

Answer 13

Constructive Interference

Question 14

Results when the waves are out phase

Waves out of phase cancel each other

Answer 14

Destructive Interface

Question 15

● Occurs when two waves of the same frequency and amplitude but traveling in opposite direction interfere
● Does not appear to be moving in either direction

Answer 15

Standing wave

Question 16

points that never move at all; manifests destructive interference

Answer 16

Node

Question 17

points that have greatest amplitude; manifests constructive interference

Answer 17

Antinode

Question 18

Does not transfer energy – there is local flow of energy from each node to the next; but average energy transfer is zero.

Answer 18

Standing wave

Question 19

Each frequency with its associated vibration pattern is called

Answer 19

Normal modes

Question 20

sequence of frequencies in which each frequency is an integer of a fundamental

Answer 20

HARMONIC SERIES

Question 21

any frequency greater than the fundamental frequency

Answer 21

OVERTONE