How would you determine the magnitude of the magnetic force on a #120 m# length of line?

An electric power line carries a current of #1100 A# in a location where the earth's magnetic field is #6.0 ✕ 10^-5 T#. The line makes an angle of #75°# with respect to the field.

1 Answer
Nov 23, 2017

Answer:

#vecF~~7.65N#

Explanation:

The magnitude of the magnetic force is given by #vecF=vec(B)vec(I)lsintheta#, where:

  • #vecF# is the vector value for the magnetic force (#N#)
  • #vec(B)# is the vector value for the magnetic field strength (#T#)
  • #vecI# is the vector value for the current (#A#)
  • #l# is the length of material being acted upon by the magnetic field (#m#)
  • #theta# is the angle between the current and magnetic field (hence why the vector arrows are needed)

The arrows are there for the vector values, as #F#, #B#, and #I# are part of a vector diagram:
https://www.slideshare.net/cjordison/magnetic-force-field-2012

Using the equation, we get:
#vecF=(6*10^(-5))(1100)(120)sin75~~7.65N#