Answer to Question #231894 in Electricity and Magnetism for Arvin Shopon

Question

The strength of the homogeneous magnetic field was measured by the following experimental arrangement:  The rectangular conductor loop was partially introduced into the magnetic field as shown. The wire loop was hung on a computer power sensor and calibrated to show zero. When the current in the conductor loop was 325 mA, the force sensor showed a reading of 32.9 mN. Based on this, what was the magnetic flux density of the magnetic field? The magnetic field at the current loop was approximately homogeneous.

Answer 1

The force is

$$F=IBL,$$

if the length of the wire is L, the field is

$$B= \frac{F}{IL}=0.101/L.$$