Standing waves (graphing) homework question

[jerad908]

Homework Statement

How much time (as a fraction of the waves' period) passes between point C meeting B then A? (Shown Below in attempt)

Relevant Equations

none

Points A b AND C are shown in first diagram
Im confused about question three... I feel like its related to wave length but the fractions are throwing me off.

 

[kuruman]

It is related to the wavelength. Point C travels to the left a distance of one wavelength in time T.
When point C coincides with B, start your timer. What fraction of a wavelength has C covered when it coincides with A? That will tell you what fraction of the period T the timer shows when that happens. Careful!

 

[jerad908]

but how would we use a timer if only given a diagram

 

[kuruman]

It's an imaginary timer. This is a "thought" experiment.

 

[jerad908]

since the wavelength is 6 units and C moves over 6 units to meet B would it just be 1?

 

[jerad908]

And then when it meets with point A, it further covers 1/4 of T?

 

[kuruman]

And then when it meets with point A, it further covers 1/4 of T?

Correct.

 

[jerad908]

and just to confirm, when C and B meet, 1/1 T is covered? - (from the very starting position to when C and B have coincided )

 

[kuruman]

and just to confirm, when C and B meet, 1/1 T is covered?

Not what it looks like to me. What is the distance between C and B? I count 13 squares. How many wavelengths is that?

 

[jerad908]

Thats two wave lengths plus 1/6 of a wavelength