1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Help with interference question AH physics? exam tomorrow :(

  1. May 4, 2015 #1
    Could someone please explain this question to me I'll include what I thought the answer was and the actual SQA answers.

    Please can you read my answer just to see what I'm doing wrong and what I don't understand

    It's from the 2009 past paper AH physics

    Thanks so much I really appreciate any help smile.png exam tomorrow ;(

    1. The problem statement, all variables and given/known data


    2. Relevant equations

    these are gien below in my attampt and in the SQA marking scheme included below

    3. The attempt at a solution

    this is the answer given by sqa


    thanks very very very much
  2. jcsd
  3. May 4, 2015 #2


    User Avatar
    Science Advisor
    Homework Helper
    2017 Award

    Your 2 n t looks more like 4 n t and what you write down doesn't correspond to what you calculate.

    Furthermore, you and sqa both seem to know ##\lambda##. We don't.

    So: work a little less hasty, and you'll be just fine. Good luck tomorrow !
  4. May 4, 2015 #3

    sorry λ is 580nm

    thanks so much for ur reply
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted