# Traveling Waves

## Video Clips

#### Traveling Waves

RealVideo®
8:48 minutes (0:00 - 8:48)

Definition, including wavelength, wave number, frequency, period, and amplitude. Mention of electromagnetic waves as a kind of traveling wave.

Prior Knowledge: None
Instructor: Prof. Walter Lewin

#### Review: Traveling Waves

RealVideo®
7:43 minutes (17:21 - 25:04)

Equations for a traveling wave in a string, including frequency, wavelength, and wave number. Wave equations and the Poynting vector for traveling electromagnetic waves.

Prior Knowledge: Traveling Waves (beginning of video lecture 26) and Electromagnetic Waves (15:10 of video lecture 27)
Instructor: Prof. Walter Lewin

## Practice Problems

#### Wavenumber Identification

PDF
Problem on page 3

Identify the value of k (wavenumber) in a plot of cos(kx).

Prior Knowledge: Sinusoidal Waves, Wavenumber
Instructors: Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. Sen-Ben Liao

#### Traveling Wave

PDF
Problem 4

4-part problem; finding A, f, p, v, λ, ν, and sketching the wave; finding transverse speed and standing waves.

Prior Knowledge: None
Instructor: Prof. Walter Lewin

#### Standing Waves

PDF
Problem 5

4-part problem; finding λ, ν, f, p and sketching; finding transverse speed and propagation speed.

Prior Knowledge: None
Instructor: Prof. Walter Lewin

#### Sonic Pulses

PDF
Problem 6

Calculating time error for bat's measurement; scale error for methane-filled cave.

Prior Knowledge: None
Instructor: Prof. Walter Lewin

#### Sound Wave

PDF
Problem 1

How do you know sound is not an EM wave?

Prior Knowledge: None
Instructors: Dr. Peter Dourmashkin, Prof. Gunther Roland

## Exam Question

#### Traveling Wave

PDF
Problem 1

Finding the equation for a traveling wave in the x-z plane given v, A, and f.

Prior Knowledge: None
Instructor: Prof. Walter Lewin