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Electrolyte challenge

Postby Jujub94 » Mon Jan 18, 2016 3:08 pm

I have a question about figuring out the equation s for this experiment. We got our readings for the liquids tested. I was reading the next page about some equation and am totally confused. It is telling us to convert micro amps by dividing by 1,000,000. The directions said to set the multimeter to 200 micro amps for the distiller water and submerge the conductance straw in liquid and the first reading was 7.8. I am confused which number should I divide by 1,000,000. Should I divide 7.8 by 1,000,000 or the 200 micro amps I set the multimeter to and divide the 200 by 1,000,000. Please help !

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Re: Electrolyte challenge

Postby HowardE » Mon Jan 18, 2016 4:33 pm

The equation for conductance requires that you know the current in amps. Your meter either gave you a reading in milliamps or microamps, depending on how you set it. Since 1 amp = 1,000,000 microamps, you divide a microamp reading by 1 million. 1 amp = 1,000 milliamps, so you divide a milliamp readin by 1,000 to convert it to amps. You use one or the other of these divisors depending on how you set the meter. To convert your 7.8 microamps to amps, you divide it by 1,000,000.

The 200 microamp range simply means that the meter can display between 0 and 200 microamps. If the current is going to be be greater than 200 microamps, you will need to switch the meter to a higher range and read in milliamps instead.


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