Ask Experts Questions for FREE Help !
Ask
    albear's Avatar
    albear Posts: 1,594, Reputation: 222
    Ultra Member
    		  
    #1

    Jun 9, 2007, 07:21 AM
    PA04 section A qn 3
    A progressive wave in a stratched string has a speed of 20m/s and a frequency of 100Hz. What is the phase difference between two points 25mm apart?

    A) zero
    B) pi/4 rad
    c) pi/2 rad
    d) pi rad

    the ans is B but I'm not sure how to obtain it
    Capuchin's Avatar
    Capuchin Posts: 5,255, Reputation: 656
    Uber Member
    		  
    #2

    Jun 9, 2007, 07:57 AM
    Work out the wavelength, work out how many waves you can fit in your 25mm, you'll get a remainder of a wavelength and you need to work out how many radians it correponds to.
    albear's Avatar
    albear Posts: 1,594, Reputation: 222
    Ultra Member
    		  
    #3

    Jun 9, 2007, 08:16 AM
    OK so lambda =c/f =3*10^8 /100 =3*10^6

    am I going I the right direction, I don't think so should I have used lambda =ws/d
    albear's Avatar
    albear Posts: 1,594, Reputation: 222
    Ultra Member
    		  
    #4

    Jun 9, 2007, 09:47 AM
    So... am I on the right track , anyone
    albear's Avatar
    albear Posts: 1,594, Reputation: 222
    Ultra Member
    		  
    #5

    Jun 10, 2007, 09:09 AM
    Hello?
    Capuchin's Avatar
    Capuchin Posts: 5,255, Reputation: 656
    Uber Member
    		  
    #6

    Jun 11, 2007, 04:04 AM
    This is a wave in a string, not electromagnetic radiation, the speed isn't c.
    mmjdny's Avatar
    mmjdny Posts: 13, Reputation: 1
    New Member
    		  
    #7

    Jun 13, 2007, 10:24 AM
    100cycles per second also 20m per second so ::::
    20m:100cycles:: 25E-3:?
    100X25E-3/20 = 1/8cycle=Pi/4 rad
Not your question? Ask your question View similar questions
 

Question Tools Search this Question
Search this Question:

Advanced Search


Check out some similar questions!

Quick pregnancy after C-section [ 1 Answers ]

I had my baby by C-section in Dec 06 and my cycle's been regular since Feb 07. I'm worried I may have accidentally gotten pregnant 2 weeks ago.Since there should be a 1 yr gap at least before the next pregnancy, how will this affect me? What are my options?

Probability section [ 3 Answers ]

How many ways are there to get a 12 with 3 dices?

I moved this because I think it belongs in this section [ 10 Answers ]

I apologize for the length of this but there is so much history it is hard to summarize please bear with me. I am currently being taken to court for child support. It is in regards to my 2 oldest children who will be 12 and 10 this summer. They have been living with my ex husband since sept of...

View more questions Search