Q3: Transcranial magnetic stimulation (TMS) is a noninva- sive technique used to stimulate regions of the human brain (Figure P31.3). In TMS, a small coil is placed on the scalp and a brief burst of current in the coil pro- duces a rapidly changing magnetic field inside the brain. The induced emf can stimulate neuronal activ- ity.
(a) One such device generates an upward magnetic field within the brain that rises from zero to T in ms. Determine the induced emf around a horizon- tal circle of tissue of radius mm.
(b) What If? The field next changes to T downward in 80.0 ms. How does the emf induced in this process compare with that in part (a)?
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