Two Long Parallel Wires That Are $0.30 \mathrm {~m}$ Apart Carry Currents Of

Multiple Choice

Two long parallel wires that are $0.30 \mathrm {~m}$ apart carry currents of $5.0 \mathrm {~A}$ and $8.0 \mathrm {~A}$ in the opposite direction. Find the magnitude of the force per unit length that each wire exerts on the other wire and indicate if the force is attractive or repulsive. $\left( \mu _ { 0 } = 4 \pi \times 10 ^ { - 7 } \mathrm {~T} \cdot \mathrm { m } / \mathrm { A } \right)$

A) $7.2 \times 10 ^ { - 5 } \mathrm {~N}$ repulsive
B) $2.7 \times 10 ^ { - 5 } \mathrm {~N}$ attractive
C) $2.7 \times 10 ^ { - 5 } \mathrm {~N}$ repulsive
D) $7.2 \times 10 ^ { - 5 } \mathrm {~N}$ attractive
E) $3.4 \times 10 - 5 \mathrm {~N}$ attractive