Patients undergoing an MRI occasionally report seeing flashes of light. Some practitioners assume that this results from electric stimulation of the eye by the emf induced by the rapidly changing fields of an MRI solenoid. We can do a quick calculation to see if this is a reasonable assumption. The human eyeball has a diameter of approximately 25 mm. Rapid changes in current in an MRI solenoid can produce rapid changes in field, with AB/At as large as 60 T/s. For the steps and strategies involved in solving a similar problem, you may view a Video Tutor Solution. ▼ Express your answer with the appropriate units. E = Submit Part B ON I μА Value Request Answer Units ? How does this compare to the 15 mV necessary to trigger an action potential? O This amount of emf is absolutely inadequate to trigger an action potential. O This amount of emf is almost adequate to trigger an action potential. O This amount of emf is inadequate to trigger an action potential. O This amount of emf is more than adequate to trigger an action potential.

Patients undergoing an MRI occasionally report seeing flashes of light. Some practitioners assume that this results from electric stimulation of the eye by the emf induced by the rapidly changing fields of an MRI solenoid. We can do a quick calculation to see if this is a reasonable assumption. The human eyeball has a diameter of approximately 25 mm. Rapid changes in current in an MRI solenoid can produce rapid changes in field, with AB/At as large as 60 T/s. For the steps and strategies involved in solving a similar problem, you may view a Video Tutor Solution. ▼ Express your answer with the appropriate units. E = Submit Part B ON I μА Value Request Answer Units ? How does this compare to the 15 mV necessary to trigger an action potential? O This amount of emf is absolutely inadequate to trigger an action potential. O This amount of emf is almost adequate to trigger an action potential. O This amount of emf is inadequate to trigger an action potential. O This amount of emf is more than adequate to trigger an action potential.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter16: Electromagnetic Waves

Section: Chapter Questions

Problem 44P: If electric and magnetic field strengths vary sinusoidally in time at frequency 1.00 GHz, being zero...

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