what does phase-shift mean??? Watch

thats_my_poison
Badges: 1
Rep:
?
#1
Report Thread starter 12 years ago
#1
the title pretty much says it all. i've looked in my maths textbook, ive googled it, etc, but i cant find the answer. please help. my exam's tomorrow morning
0
reply
AlphaNumeric
Badges: 10
Rep:
?
#2
Report 12 years ago
#2
If you've a plane wave written as \psi(x,t) = Ae^{i(kx-vt)} than a phase shift would be multiplying \psi(x,t) by e^{i\theta}. The phase shift amount is \theta.
0
reply
gyrase
Badges: 0
Rep:
?
#3
Report 12 years ago
#3
A transformation under which an oscillating function will move left/right with respect to the x-axis. E.g. sin(x-30) is a phase shift of sin(x) by 30.
0
reply
thats_my_poison
Badges: 1
Rep:
?
#4
Report Thread starter 12 years ago
#4
dont really understand either definition, but say there is a graph of y = 3cos (6theta + 180), would the phase shift be -30 because it's -180/6???
0
reply
AlphaNumeric
Badges: 10
Rep:
?
#5
Report 12 years ago
#5
In that case, if you've a sin or cos function with the transformation \theta \to \theta + \theta_{0}. The shift is \theta_{0}.
0
reply
thats_my_poison
Badges: 1
Rep:
?
#6
Report Thread starter 12 years ago
#6
(Original post by AlphaNumeric)
In that case, if you've a sin or cos function with the transformation \theta \to \theta + \theta_{0}. The shift is \theta_{0}.
so is my answer correct? btw, this is in reference to c2
0
reply
Trevor 12345
Badges: 0
Rep:
?
#7
Report 12 years ago
#7
(Original post by alison_141288)
so is my answer correct? btw, this is in reference to c2
yes

y = 3cos (6theta + 180)

would be a shift of -30 of the graph y=3cos(6theta)
0
reply
Cexy
Badges: 0
Rep:
?
#8
Report 12 years ago
#8
Yup, the phase shift is -30 (or perhaps 30 depending on your conventions, but I'd say -30).

The function is y=\sin(6\theta+180)=\sin(6(\thet  a+30))

Thus compared to the function y=\sin 6\theta you've shifted the phase by thirty degrees.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • Cranfield University
    Cranfield Forensic MSc Programme Open Day Postgraduate
    Thu, 25 Apr '19
  • University of the Arts London
    Open day: MA Footwear and MA Fashion Artefact Postgraduate
    Thu, 25 Apr '19
  • Cardiff Metropolitan University
    Undergraduate Open Day - Llandaff Campus Undergraduate
    Sat, 27 Apr '19

Have you registered to vote?

Yes! (254)
38.84%
No - but I will (45)
6.88%
No - I don't want to (47)
7.19%
No - I can't vote (<18, not in UK, etc) (308)
47.09%

Watched Threads

View All