How can you use an ammeter to measure a voltage of 5.0 V?

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To measure a voltage of 5.0 V using a 500 microA ammeter, a resistor R must be connected in series with the ammeter. The relationship between voltage, current, and resistance is defined by Ohm's Law (V = IR). By rearranging this equation, R can be calculated as R = V/I, resulting in R = 5 V / (500 x 10^-6 A), which equals 10,000 Ohms. This setup allows the ammeter to reach full scale for the specified voltage. The calculation is confirmed to be correct.
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Homework Statement



A circuit you're building needs a voltmeter that goes from 0 to a full-scale reading of 5.0 V. Unfortunately, the only meter in the storeroom is an ammeter that goes from 0 to a full-scale reading of 500 microA. It is possible to use this meter to measure voltages by putting in a measuring circuit as shown in the figure. (Figure attached)
What value of R must you use so that the meter will go to full scale when the potential difference Delta V is 5.0 V? Assume that the ammeter is ideal.

Homework Equations



I = VR

The Attempt at a Solution

 

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When you connect the ammeter with a high resistance R in series across a measuring circuit, the current in the ammeter should be 500 mA. Delta V is given, Find R.
 


Delta V = IR
I = 500 microA = 500*10^-6 A
Delta V = 5 V
R = V/I = 5 V/(500*10^-6 A) = 1*10^4 Ohm

Is this correct?
 


Yes.
 


I appreciate it.
 
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