Question

The drawing shows a type of flow meter that can be used to measure the speed of blood in situations when a blood vessel is sufficiently exposed (e.g., during surgery). Blood is conductive enough that it can be treated as a moving conductor. When it flows perpendicularly with respect to a magnetic field, as in the drawing, electrodes can be used to measure the small voltage that develops across the vessel. Suppose the speed of the blood is 0.35 m/s and the diameter of the vessel is 5.6 mm. In a 0.57-T magnetic field what is the magnitude of the voltage that is measured with the electrodes in the drawing?

Answer 1

formula for induced voltage is

induced voltage = B l v

given that

B = 0.57 T and l = 5.6 mm = 5.6 *10 ^-3 m

v = 0.35 m/sec

induced voltage = 0.57 *5.6 *10 ^-3 * 0.35

= 1.1172 *10 ^-3 V