Lesson 35
Name: etp       Section: T1       Start Time: 16:16:10       Instructor: Dr Brian M. B_Patterson       Course: 110      

1) Identify figures (a) and (b) as longitudinal or transverse waves.
Explain what distinguishes a longitudinal from a transverse wave.
(Section 16-2 in your text discusses these different types of waves.)

2) A certain transverse traveling wave on a string can be represented by the following equation

where y is the displacement of the string, x is position of a point along the string, and t is the time.

What are the units of the coefficients of the x-term and the t-term in the above expression? What do we call those coefficients?

3) Be sure the simulation has finished loading before you begin.

Test your function for g(x,t) here. g(x,t)=

Consider the wave f(x,t) in the top panel of the simulation. What are its (i) amplitude, (ii) wavelength, (iii) frequency, (iv) wavenumber, and (v) speed? Please briefly explain how you arrive at your answer (what you measured, counted, etc.) (Simulation Hints! Click the "Forward" button to run the simulation. The controls at the bottom work like VCR controls. You can click and drag inside the animation to read the coordinates in order to obtain numerical values for use in your equations. A running time display is in the top left corner of the top panel. Also note that you may want to stop the animation in order to measure things like the wavelength.)

Hints: Remember that a traveling wave y(x,t) can be described by y(x,t) = A sin (kx + wt), where y is the amplitude of the wave, k is the wavenumber ( = 2p/wavelength), x is the position in meters, w is the angular frequency ( = 2p/period), and t is the time in seconds. The speed of the wave is just the rate at which a certain point on the wave (e.g., a point of maximum amplitude) moves along, and is given by v = wavelength/period.

Note: If you'd like a 'sneak preview' of wave superposition, click the "Enter" button next to the small text area at the bottom of the simulation. The f(x,t) function [top panel] and the g(x,t) function [middle panel, and corresponding to the equation you enter in the textarea] are added together to produce a new wave function f(x,t)+g(x,t) [bottom panel]. Also, feel free to 'play' with the parameters in the equation to get a feel for what each affects/represents.

Below is a space for your thoughts, including general comments about today's assignment (what seemed impossible, what reading didn't make sense, what we should spend class time on, what was "cool", etc.):

You may change your mind as often as you wish. When you are satisfied with your responses click the SUBMIT button.

I received no help from anyone on this assignment.
I received help from someone on this assignment (document in comments section).