Why isn't the phase difference pi/2 in part ii?

[kelvin macks]

Homework Statement

for part ii , why the phase difference isn't =pi/2 ? I'm having problem uploading the photo .https://www.flickr.com/photos/123101228@N03/14289633415/

Homework Equations

The Attempt at a Solution

 

[haruspex]

In the second graph under ii, you appear to have pencilled in two arrows exactly one complete cycle apart. How far is that in terms of radians?

 

[kelvin macks]

i am not sure the penciled arrows is correct or not? on the top diagram in ii, both arrow at 0 and pi pointed downwards, whereas the below diagram pionted upwards. i did this beacuse i refer to the notes on other old book , but i don't know the reason why should i do this. can you expalin why?

 

[kelvin macks]

...deleted

 

[haruspex]

i am not sure the penciled arrows is correct or not? on the top diagram in ii, both arrow at 0 and pi pointed downwards, whereas the below diagram pionted upwards. i did this beacuse i refer to the notes on other old book , but i don't know the reason why should i do this. can you expalin why?

I wasn't asking why the arrows are there, that doesn't matter. I'm just asking how far apart you think they are as a number of radians, i.e. their phase difference. From your reply, you seem to think they're π apart. They're one complete cycle apart, which is 2π.

 

[kelvin macks]

sorry , i should nt have asked this question. i realized my mistake.