A patient is undergoing open heart surgery

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A sustained current of 25 microAmps (uA) through the heart can be fatal, and with a heart resistance of 250 Ohms, the minimum dangerous voltage is calculated to be 6.25 milliVolts (mV) or 0.00625 Volts. There was some confusion regarding the units used, particularly whether resistance was in Ohms and current in microAmps. One participant calculated the voltage using a different method, arriving at 1/160 V, which is equivalent to 0.00625 V. Clarification on unit usage is advised to avoid misunderstandings. Accurate communication of electrical parameters is crucial in medical contexts.
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1 - a patient is undergoing open heart surgery . A sustained current as small as 25 muA passing through the heart can be fatal . Assme that the heart has a constant resistonce of 250 ; detrmine the mininum voltage that poses a danger to the parient .

v= 25 X 250 = 6250
 
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wanted1 said:
1 - a patient is undergoing open heart surgery . A sustained current as small as 25 muA passing through the heart can be fatal . Assme that the heart has a constant resistonce of 250 ; detrmine the mininum voltage that poses a danger to the parient .

v= 25 X 250 = 6250

You need to use proper units in order for your question and answer to be unambiguous. What are the units for resistance? Ohms? What are muA? Does this mean microAmps, or milli-microAmps, or milli-uA (whatever a uA is)? What are the unit for your final answer? Volts, milliVolts or microVolts?

I'll assume that you asking the following ...

"A sustained current of 25 microAmps can be fatal. If the heart has a resistance of 250 Ohms, determine the minimum voltage that can kill.

V = 25 uA x 250 Ohms = 6250 uA = 6.25 milliVolts = 0.00624 Volts.
 
Hi

but I find the answer lile this ??

25 X 250 X(1/10^6) = 1 /160 V

why the answer not as your ?
 
wanted1 said:
Hi

but I find the answer lile this ??

25 X 250 X(1/10^6) = 1 /160 V

why the answer not as your ?

You do get the same answer because 1/160 V is equal to 0.00625 V. (I have a typo in my above post: 0.00624 V should be 0.00625 V)

I would still recommend a little better clarity on your expression. It's not clear if you are using 25 Amps and 250 microOhms, or 26 microAmps and 250 Ohms. Obviously, it's the latter, but the way you write it can confuse someone.
 

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