Hey there! Sign in to join this conversationNew here? Join for free
x Turn on thread page Beta

Physics - Electromagnetic Induction Problems watch

Announcements
    • Thread Starter
    Offline

    1
    ReputationRep:
    I've just finished revising this topic and then started on some questions BUT I got every single one wrong! I Don't know where I'm going wrong and would be greatful if someone could answer these questions for me and show the working out with comments.
    Attached Images
     
    Offline

    1
    ReputationRep:
    ok flux linkage (amount of flux) = area * flux density

    9.7) 0.15* (1^-2)^2
    =15^-6W

    9.8) 5^-3*2.9^11
    =1.45^9W

    does this make any sense?
    Offline

    0
    ReputationRep:
    9.7:

    Flux = BA = 0.15*0.01*0.015 = 2.25x10^-5 Wb

    9.8:

    just do area * flux again

    9.9

    Not 100% sure, but as a guess try pi*0.025^2 (cross sectional area) then times that by the flux density


    9.10

    Find area from 0.05 * 0.075

    Flux linkage =nBA = 120*1.2*0.05 * 0.075

    Am i right on any of those (I hope so!!!)
    Offline

    0
    ReputationRep:
    (Original post by Speciez99)
    ok flux linkage (amount of flux) = area * flux density

    9.7) 0.15* (1^-2)^2
    =15^-6W

    9.8) 5^-3*2.9^11
    =1.45^9W

    9.9) area = Pi*r^2
    Pi(5^-2)^2
    2.5^-3Pi
    2.5^-3*Pi*2^-3
    =15.7^-6W

    9.10)area = 5^-2*75^-2
    0.0375m^2
    12*0.0375 (or is it 1.2T?)
    =0.45W

    does this make any sense?
    that is absolute ****ing *******s my answers are complete opposite to yours and im an A grade physics student - seriously if you dont know what you're talking about plz stfu
    Offline

    0
    ReputationRep:
    oh dazzy plz praise my answers...PLEASE!!!
    Offline

    0
    ReputationRep:
    ok for absolute starters 9.7:

    Flux = BA whic is 0.15 X ( 1.5 x 10^-2 ) remmeber base units are in metres which gives an answer of 2.25 x 10^-5 Wb


    for 9.8

    Flux = BA 5 x 10^-5 x 2.9 x 10^11

    = 1.45 x 10^7 Wb

    for 9.9
    NFlux = BAN

    N = 2 x 10^-3 x 15.7 x 10^-4 x 200

    = 6.28 x 10^-4 Wb


    and for 9.10

    NFlux = BAN = 1.2 x 37.5 x 10^-4 x 120

    = 0.54 Wb
    Offline

    0
    ReputationRep:
    see i didnt think in 9.9 you times by the number of turns, because that's flux linkage rather than flux.....although you may be right, i havent revised that bit
    Offline

    0
    ReputationRep:
    (Original post by Willa)
    see i didnt think in 9.9 you times by the number of turns, because that's flux linkage rather than flux.....although you may be right, i havent revised that bit
    your working is fine
    yes always Nflux = BAN
    Offline

    1
    ReputationRep:
    (Original post by dazzyaa911)
    that is absolute ****ing *******s my answers are complete opposite to yours and im an A grade physics student - seriously if you dont know what you're talking about plz stfu
    haha, if only you knew... that would be quite insulting if there was actually a grain of truth in it. Firstly i apoligies to nofronting if i have mislead him on the last 2 questions, i am not focused at all. Secoundly whats with the swearing, no where have i clammed to be some sort of God of physics and everyone gets things wrong so whats with the insults?
    Offline

    0
    ReputationRep:
    (Original post by Speciez99)
    haha, if only you knew... that would be quite insulting if there was actually a grain of truth in it. Firstly i apoligies to nofronting if i have mislead him on the last 2 questions, i am not focused at all. Secoundly whats with the swearing, no where have i clammed to be some sort of God of physics and everyone gets things wrong so whats with the insults?
    if you're going to get him into BAD HABBITS then don't let your fingers touch the keyboard
    Offline

    1
    ReputationRep:
    (Original post by dazzyaa911)
    if you're going to get him into BAD HABBITS then don't let your fingers touch the keyboard
    so you have not explained at all why you need to swear in an offence manner in this post at all?
    and secoundly how is looking at the wrong answer going to get him into bad habits if he eventualy gets the wrong answer, i made a mistake and i am sorry for that, and everyone does at some point. you seem to think i am shite at physics and i seriously resent that.
    Offline

    0
    ReputationRep:
    but 9.9 asks for flux, not flux linkage

    the number of turns is related to the flux density, and since they give that to you anyway, it's not required
    I'm pretty sure it's just BA, not nBA (In this case that is)
    Offline

    0
    ReputationRep:
    yo
    one question about q9.9
    i got it all except this one
    why didnt you use

    NFlux = BIAN ??
    cause mine was
    Nflux = (2-10^-3) x (200) x (2) x (0.05x0.25)
    = 0.01Wb
    Offline

    0
    ReputationRep:
    (Original post by Speciez99)
    so you have not explained at all why you need to swear in an offence manner in this post at all?
    and secoundly how is looking at the wrong answer going to get him into bad habits if he eventualy gets the wrong answer, i made a mistake and i am sorry for that, and everyone does at some point. you seem to think i am shite at physics and i seriously resent that.
    because its not good when someone teaches somebody else bad habbits, PERIOD.

    if you are feeling ' unfocussed ' then please, do not answer.
    Offline

    0
    ReputationRep:
    since when does NFlux = BIAN ....never seen current being involves in my life!!! Please explain
    Offline

    1
    ReputationRep:
    (Original post by dazzyaa911)
    because its not good when someone teaches somebody else bad habbits, PERIOD.

    if you are feeling ' unfocussed ' then please, do not answer.
    i am not delebrately teaching him bad habits, when i answered this thread i had no idea whether anyone else was and my intentions were only to do good, so you are still acussing me of being rubbish physics for which you still havent apologied
    Offline

    0
    ReputationRep:
    (Original post by MalaysianDude)
    yo
    one question about q9.9
    i got it all except this one
    why didnt you use

    NFlux = BIAN ??
    cause mine was
    Nflux = (2-10^-3) x (200) x (2) x (0.05x0.25)
    = 0.01Wb
    its definately not 0.01Wb, thats way way WAY TOO BIG
    Offline

    0
    ReputationRep:
    (Original post by Speciez99)
    i am not delebrately teaching him bad habits, when i answered this thread i had no idea whether anyone else was and my intentions were only to do good, so you are still acussing me of being rubbish physics for which you still havent apologied
    where did i say you were rubbish at physics? and why do i need to apologise? omg i didn't hurt you did i by correcting you?
    Offline

    0
    ReputationRep:
    you just multiplied everything together...regardless of whether BIAN is a correct formula or whatever....length has nothing to do with this i'm sure!?
    Offline

    1
    ReputationRep:
    (Original post by dazzyaa911)
    where did i say you were rubbish at physics? and why do i need to apologise? omg i didn't hurt you did i by correcting you?
    (Original post by dazzyaa911)
    that is absolute ****ing *******s my answers are complete opposite to yours and im an A grade physics student - seriously if you dont know what you're talking about plz stfu
    the bit where you say i dont know anything about physics is the bit that says if you don't know what you are talking about plz stfu
    and you need to apologies because on that matter you are wrong
 
 
 
Poll
Do you agree with the proposed ban on plastic straws and cotton buds?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.