22.7 Magnetic Force on a Current-Carrying Conductor

(a) A DC power line for a light-rail system carries 1000 A at an angle of $\text{30}.\text{0}º$ to the Earth’s $\text{5}.\text{00} \times \text{10}^{- 5} -\text{T}$ field. What is the force on a 100-m section of this line? (b) Discuss practical concerns this presents, if any.

A wire carrying a 30.0-A current passes between the poles of a strong magnet that is perpendicular to its field and experiences a 2.16-N force on the 4.00 cm of wire in the field. What is the average field strength?

(a) What is the angle between a wire carrying an 8.00-A current and the 1.20-T field it is in if 50.0 cm of the wire experiences a magnetic force of 2.40 N? (b) What is the force on the wire if it is rotated to make an angle of $\text{90}º$ with the field?