Support Forums Today's Posts

Get Advice Connect with TeenHelp Resources
HelpLINK Facebook     Twitter     Tumblr     Instagram    Hotlines    Safety Zone    Alternatives

You are not registered or have not logged in

Hello guest! (Not a guest? Log in above!)

As a guest on TeenHelp you are only able to use some of our site's features. By registering an account you will be able to enjoy unlimited access to our site, and will be able to:

  • Connect with thousands of teenagers worldwide by actively taking part in our Support Forums and Chat Room.
  • Find others with similar interests in our Social Groups.
  • Express yourself through our Blogs, Picture Albums and User Profiles.
  • And much much more!

Signing up is free, anonymous and will only take a few moments, so click here to register now!

Education and Careers Work of any kind can get stressful at times. Ask in this forum if you need help with coursework, applications, and more.

Closed Thread
Thread Tools Search this Thread Rate Thread
  (#1 (permalink)) Old
Jagger Offline
Welcome me, I'm new!
Jagger's Avatar
Name: Jagger
Age: 25
Gender: Male
Location: United Kingdom

Posts: 8
Join Date: March 29th 2009

Change in magnetic flux - May 27th 2009, 09:54 AM

Ok, so, I was in my physics lesson yesterday and we're doing about magnetic flux. I know that you get a p.d. whenever you move a conductor in a magnetic field.

What I'm wondering about is - if you have a perfect band/circle and you spin it around its own axis (so that whenever you look at it, it is exactly the same in all directions), would that create a p.d.?

I'm confused because on the one hand you are moving it, which would suggest yes, but conversely it's exactly the same whenever it's turned round, so you aren't really changing anything.

Has anyone got any ideas?
  (#2 (permalink)) Old
molliegym Offline
Junior TeenHelper
molliegym's Avatar
Name: Molly
Age: 29
Gender: Female
Location: NJ

Posts: 252
Blog Entries: 1
Join Date: January 6th 2009

Re: Change in magnetic flux - May 27th 2009, 12:54 PM

I learned magnetic flux as the number of magnetic field lines per a certain area. To have a change in magnetic flux, you have to have a change in the number of magnetic field lines in the area. The equation is magnetic flux = B*A*cos(theta), where B is the magnetic field strength, A is the area of the loop, and theta is the angle of the loop to the magnetic field lines. So if you have a circle that's rotating about it's own axis (like how a hula-hoop is- imagine a "perfect" hula hoop going at a constant pace around your hips without moving up or down), I think there would be no change in magnetic flux.

(P.S.- if this is wrong, I'm so sorry- I just took the AP Physics B exam, but electricity and magnetism was the hardest part for me).

[IMG]file:///C:/Users/MOLLYH%7E1/AppData/Local/Temp/moz-screenshot-2.jpg[/IMG]A few clicks will help @TWLOHA win $1 Million for suicide prevention. Please share this with others. Vote here:http://bit.ly/7si7Be

My music

I never conquered, rarely came
Tomorrow holds such better days

Check out my blog, Cold Fusion, with music news, reviews, and other related musings.

  Send a message via AIM to molliegym Send a message via MSN to molliegym  
  (#3 (permalink)) Old
pbandjay Offline
Welcome me, I'm new!
pbandjay's Avatar
Name: Joseph
Age: 33
Gender: Male
Location: Iowa, US

Posts: 24
Join Date: March 29th 2009

Re: Change in magnetic flux - May 30th 2009, 08:56 AM

Are you using conceptual- or calculus-based physics?

Since your disc is not a closed surface, a change in magnetic flux can cause a force, which by Faraday, can be reduced to a simple derivative of the flux through the surface. If the flux through the surface is zero or constant, the derivative is zero and therefore a force will not result. I assume you did not learn it this way since looking at it from a calculus standpoint, the magnetic flux is a surface integral of the magnetic field itself, and the resulting force is a path integral which reduces to the derivative of the surface integral.

One neat formula is by Gauss: If the surface integral is around a closed surface then it is equal to zero and there is no magnetic flux.
  Send a message via AIM to pbandjay Send a message via MSN to pbandjay Send a message via Skype™ to pbandjay 
  (#4 (permalink)) Old
King of D Devil
Average Joe
King Of Iron Fist's Avatar
Name: Wonderboy
Age: 30
Gender: Male
Location: INDIA

Posts: 114
Join Date: January 8th 2009

Re: Change in magnetic flux - June 1st 2009, 07:04 AM

i also have physics and i dont know any thing about it but if you have any problem in maths then tell me

the world
is just

  Send a message via MSN to King Of Iron Fist Send a message via Yahoo to King Of Iron Fist Send a message via Skype™ to King Of Iron Fist 
Closed Thread


change, flux, magnetic

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Rate This Thread
Rate This Thread:

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All material copyright 1998-2020, TeenHelp.
Terms | Legal | Privacy | Conduct | Complaints | Mobile

Powered by vBulletin®.
Copyright ©2000-2020, Jelsoft Enterprises Ltd.
Search engine optimization by vBSEO.
Theme developed in association with vBStyles.