Current and drift speed (18-3)

Question 1 of 5

Question

Speed at which charges drift through the wire

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Review

Let’s see how to find the magnitude of the magnetic force on a current-carrying wire, such as a segment of the coil in Figure 19-9b. Figure 19-10 shows a straight wire of length $\ell$ that carries a current $i$ . A magnetic field $\vec{B}$ points at an angle $\theta$ to the direction of the current, and has the same value along the entire length of the wire. We learned in Section 18-2 that the current in the wire is related to the speed at which individual charges drift through the wire: