11.1/2 Progressive waves/wave properties

Question 1

What is a progressive wave?

Answer 1

A progressive wave is a means of transferring energy from one place to another without a transfer of matter between the two points.

Question 2

What are the two types of waves?

Answer 2

-Longitudinal
-Transverse

Question 3

What are transverse waves?

Answer 3

A transverse wave is a type of wave where the direction of oscillations occur perpendicular to the direction of wave propagation.

Question 4

What are the names for displacements of a transverse wave?

Answer 4

-Crest/peak; maximum displacement from equilibrium.
-Trough; minimum displacement from equilibrium.

Question 5

What is the name of the distance from one point of a wave to a corresponding point on the next wave?

Answer 5

Wavelength; examples where a wavelength could be measured from: two peaks/crests or two troughs. The wavelength of a wave determines the spatial extent of one complete cycle, known as a period, of the wave.

Question 6

What is the name of the distance between the maximum/minimum displacement point and the equilibrium?

Answer 6

Amplitude; determines the energy carried by the wave, with larger amplitudes corresponding to higher energy levels.

Question 7

What is a period and what is frequency?

Answer 7

The period(T) of a transverse wave is the time taken to complete one full cycle of oscillation. It is measured in units such as seconds(s). The frequency of a transverse wave is the number of complete cycles or oscillations that occur per unit time. It is measured in units of hertz(Hz), which represents cycles per second. The period and frequency are inversely related, with frequency(f) being the reciprocal of the period (T): f = 1/T.

Question 8

How is wave speed calculated?

Answer 8

v=fλ
wave speed = frequency x wavelength
1ms^-1 = 1Hz or 1s^-1 x 1m
For Electromagnetic waves, the speed is always 3.00x10^8 ms^-1.

Question 9

What types of transverse waves are there?

Answer 9

-Electromagnetic; Radio, Micro, Infrared(IR), Visible light, Ultraviolet(UV), X-ray, Gamma radiation
-Surface Water
-Seismic S-waves
-String or Rope Waves

Question 10

What are longitudinal waves?

Answer 10

A longitudinal wave is a type of wave where the direction of oscillations occur parallel to the direction of wave propagation.

Question 11

What are the unique properties of longitudinal waves?

Answer 11

Longitudinal waves consist of alternating regions of compression and rarefaction. In the compression regions, the particles are close together and have higher densities, while in the rarefaction regions, the particles are spread apart and have lower densities.

Question 12

What types of longitudinal waves are there?

Answer 12

-Sound
-Seismic P-waves
-Pressure Waves (e.g., in fluids)
-Ultrasound

Question 13

What are the similarities and differences between transverse and longitudinal waves?

Answer 13

Similarities:
-they are progressive waves
-they transfer energy
Differences:
-Longitudinal: oscillations are parallel to direction of energy transfer; have rarefactions and compressions
-Transverse: oscillations are perpendicular to direction of energy transfer; have peaks/crests and troughs

Question 14

Describe how you could use a slinky to model a transverse and longitudinal wave.

Answer 14

Transverse: fix one end of the slinky and on the other end move the slinky up and down multiple times or move the slinky perpendicular to its body.
Longitudinal: fix one end of the slinky and on the other end move the slinky backwards and forwards or parallel to its body.

Question 15

Suggest why the speed of sound is faster through a denser medium.

Answer 15

The particles are closer together therefore stronger restoring force/vibrations are passed more rapidly from one particle to the next.

Question 16

What is phase difference?

Answer 16

Phase difference describes the difference between the
displacements of the particles along a wave, or the difference between the displacements of the particles on different waves. It is most often measured in degrees or radians.
ϕ=2π(x/λ) or (x/λ)*360° (2π(radians)=360°)

Question 17

Plan an experiment to determine the frequency of sound emitted from a whistle.

Answer 17

Connect a microphone to an oscilloscope. Blow the whistle and record the number of divisions (n) between successive peaks/crests of the signal displayed on the oscilloscope. Find the period (T) by dividing n by the time base and use the equation f=1/T to find the frequency.