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Homework Help: Which circuit shows the correct connection and values?

  1. Sep 15, 2018 #1
    1. The problem statement, all variables and given/known data
    Question:
    For the circuits shown in Fig. 6, voltage meters and ampere meters are used to measure
    the voltage across the load and their current flow. If the Red Probe is plugged into the “+”
    terminal of the voltage meter and ampere meter, which circuit(s) show both the correct
    connections and measurement values? State all correct answers.
    Screenshot_7.png
    2. Relevant equations
    I= V/R

    3. The attempt at a solution
    I have figured out that circuit D is correct.
    Circuit F is wrong due to incorrect method of connecting the voltmeter and ammeter.
    Circuit A and E has wrong polarities in one of their values.
    Now Circuits B and D are tricky for me. Circuit B's voltmeter has a reading which is only 0.1 V lower than the EMF. Is this still considered correct?
    As for Circuit D, The value of current I got through calculation was -0.91 A. Ammeter, however, shows a reading of -1 A. I am confused on whether or not this -1 A value is a rounded off answer. Can somebody please guide me on these 2 circuits.
     
  2. jcsd
  3. Sep 16, 2018 at 6:38 AM #2

    phinds

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    Gold Member

    correct
    That's not the only thing wrong with E, but yes they are both wrong
    No, why would it be? These are obviously intended as ideal circuits so what you see is what you get.
    It appears that you are talking here about E, not D.

    How about C?
     
  4. Sep 16, 2018 at 6:39 AM #3

    NascentOxygen

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    Staff: Mentor

    If current is -0.91A then a meter reading of -1A could not be considered acceptable. I'd say.
     
  5. Sep 16, 2018 at 6:42 AM #4

    phinds

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    Gold Member

    Check out how the meters are hooked up (ignore the numbers)
     
  6. Sep 16, 2018 at 9:45 AM #5
    Ah ok. Thanks for the clarification. Yeah I was talking about E for the -0.91 A one, my bad.
    C is wrong because the voltmeter's connections are reversed. it should show a negative value.
     
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