Question

An electromagnetic flow meter is used to measure the blood flow in a vessel. The diameter of vessel is 10 mm and the flux density across the electrode is $\pi mm$. If the output voltage for a particular flow rate is 1mV then the flow rate in $m{m}^3/s$ is ?

• A. 2.5

Answer 1

The correct option is A 2.5
$\text{B=flux density,}$

$l\text{= diameter,}$

$v\text{=velocity,}$

$V_0\text{= output voltage}$

$Q=v.A=v.\frac{\pi }{4}{l}^2$

$Q=\frac{V_0}{Bl}\frac{\pi }{4}{l}^2=\frac{V_0\pi l}{4B}$

$\text{Putting the given values,}$

$Q=\frac{1\times {10}^{-3}\times \pi \times 10\times {10}^{-3}}{4\pi \times {10}^{-3}}$

$Q=2.5\times {10}^{-3}$

$Q=2.5m{m}^3/s$