1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    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!

More review problems

  1. Mar 1, 2004 #1
    11) the diagram shows 3 equally spaced wires that are perpendicular to the page. the currents are equal, 2 being out of the page and 1 going into the page. rank the wires according to the magnetude of the forces on them, from least to greatest.


    . x .
    1 2 3

    12) A proton (charge e) traveling perpendicular to a mag field, experiences the same force as an alpha particle (charge 2e) which is also traveling perpendicular to the same field. the ratio of their speeds, v (proton) / v (alpha)

    My answer is 2

    13) the mag field in T a distance of 2 cm from a long straight wire carrying a current of 2 A is about

    15) 2 long parallel straight wires carry equal currents in opposite directions. At a point midway between the wires, the mag field they produce is?

    a) zero ( I picked a)
    b) non-zero and along a line connecting the wires
    c) non-zero and parallel to the wires
    d) non-zero and perpendicular to the plane of the two wires
    e) non of the above

    16) 2 long strait wires are parallel and carry current in the same direction. the currents are 8 A and 12 A and the wires are separated by .4 cm. the mag field in tesla at a point midway between teh wires is?

    18) the mag field outside a long straight current-carrying wire depends on the distance R from the wire axis according to
    a) R
    b) 1/R
    C) 1/R^2
    d) 1/R^3
    e) 1/R^3/2
     
  2. jcsd
  3. Mar 1, 2004 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Field from a current-carrying wire: Learn it!

    No. First note the symmetry between the left and right wires: they must experience the same force. Now find the B field that they exert on the middle wire.
    OK.
    Learn the expression for the field produced by a current carrying wire; look it up.
    No. Once again, you must know the field produced by a current-carrying wire. No calculation is needed here, but you do need to know what direction the field points. Compare with #11
    Same comment.
    Ditto.
     
  4. Mar 1, 2004 #3
    On #18

    B= uI/2pieR

    So the answer should be 1/R. Right?

    Nautica
     
  5. Mar 1, 2004 #4
    I am confused about this one.

    15) 2 long parallel straight wires carry equal currents in opposite directions. At a point midway between the wires, the mag field they produce is?

    a) zero
    b) non-zero and along a line connecting the wires
    c) non-zero and parallel to the wires
    d) non-zero and perpendicular to the plane of the two wires
    e) non of the above
     
  6. Mar 1, 2004 #5
    On #11 the 1,2,3 were the names of the wires. I forgot to include my answer

    2 would have the greatest and 1 and 3 would be tied. right?
     
  7. Mar 1, 2004 #6

    d
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: More review problems
  1. More Force Review! (Replies: 3)

  2. Review problem help? (Replies: 0)

  3. Some review problem (Replies: 1)

Loading...