A long wire is known to have a radius greater than 4.0 mm and to ...

[darbym82]

A long wire is known to have a radius greater than 4.0 mm and to carry a current uniformly distributed over its cross section. If the magnitude of the magnetic field is 0.285 mT at a point 4.0 mm from the axis of the wire and 0.200 mT at a point 10 mm from the axis, what is the radius of the wire?
 a. 4.6 mm
  b. 7.1 mm
  c. 5.3 mm
  d. 12 mm
  e. 10 mm

Question 2

A long, straight wire (radius = 2.0 mm) carries a current of 2.0 A distributed uniformly over a cross section perpendicular to the axis of the wire. What is the magnitude of the magnetic field at a distance of 1.0 mm from the axis of the wire?
 a. 0.40 mT
  b. 0.80 mT
  c. 0.10 mT
  d. 0.20 mT
  e. 0.75 mT

[s.meritte]

Answer to Question 1

C

Answer to Question 2

C

[darbym82]

YES! Correct, THANKS for helping me on my review

[mcarey591]

Gracias!