Results are out! Find what you need...fast. Get quick advice or join the chat
Hey! Sign in to get help with your study questionsNew here? Join for free to post

Force, current and Electric Field: How a motor rotates

Announcements Posted on
Live Q&A today at 11am: Find out about funding for NHS courses here 09-02-2016
Earn £10 in half an hour; help us test TSR's new search box 29-01-2016
  1. Offline

    ReputationRep:
    Hi, a teacher gave me a question from a edexcel past paper A2 unit 4 and i am having troubles understanding how force, current and field works on one question:

    http://www.edexcel.com/migrationdocu...e_20110127.pdf

    Question 13, A and B

    I don't understand mark scheme, so could any prove help. I'll appreciate it!
  2. Offline

    ReputationRep:
    Bump
  3. Offline

    If you could show us the mark scheme and state what it is you don't understand it would help us to answer your question.
  4. Offline

    ReputationRep:
    (Original post by Stonebridge)
    If you could show us the mark scheme and state what it is you don't understand it would help us to answer your question.
    Q13 a and b:http://www.edexcel.com/migrationdocu...s_20110309.pdf
  5. Offline

    ReputationRep:
    It might help if you indicate which part of the mark scheme you have a problem with.

    In any case, without seeing the mark scheme, this is how I'd answer the question;

    The coil turns due to the motor effect; since current is flowing through the coil and the coil is placed in a magnetic field, then there is a force acting on the coil. Using Fleming's left hand rule, we can say that the length of coil DC will have a vertical force acting up, and the length of coil BA will have a vertical force acting down, hence rotating the coil anti-clockwise. I would then draw arrows on the diagram indicating the direction and location of those forces.
  6. Offline

    ReputationRep:
    (Original post by Rysm)
    It might help if you indicate which part of the mark scheme you have a problem with.

    In any case, without seeing the mark scheme, this is how I'd answer the question;

    The coil turns due to the motor effect; since current is flowing through the coil and the coil is placed in a magnetic field, then there is a force acting on the coil. Using Fleming's left hand rule, we can say that the length of coil DC will have a vertical force acting up, and the length of coil BA will have a vertical force acting down, hence rotating the coil anti-clockwise. I would then draw arrows on the diagram indicating the direction and location of those forces.
    Very much appreciated. I have a better understanding thanks.

Reply

Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. By joining you agree to our Ts and Cs, privacy policy and site rules

  2. Slide to join now Processing…

Updated: June 19, 2012
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

Today on TSR

It's Student Money Week

Find out which Q&As are happening today

Poll
Can you drive?
Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.