- #1

greg_rack

Gold Member

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- Homework Statement
- For measuring tension, a voltmeter uses a part of the current flowing through the circuit.

Subsequently, the tension measured is just an approximation of the one present when the voltmeter is not connected.

Consider a circuit formed by two ##1550\Omega## resistors connected in series powered by a ##60.0V## battery:

\rightarrow Find the tension of the two resistors.

An analogic voltmeter has a bottom scale of ##60.0V## and uses a galvanometer with a maximum current range of ##5.00mA##:

\rightarrow Find the tension measured by this voltmeter when it's connected to the ends of the resistors.

- Relevant Equations
- ##I=\frac{V}{R}##

First and foremost, I've studied voltmeters and ammeters on my own, and online there aren't many resources to do so... forgive me in advance for eventual silly questions/doubts :)

I managed to calculate(intuitively) a tension of ##30.0V## per resistor, with basic procedures.

However, I'm finding difficulties in solving the second point.

What does the "bottom scale" mean? Isn't it simply the maximum tension that can be measured by this tool? Also, how should I use the "maximum current range" data?

Lastly: If the voltmeter must be precise, how could this result be different from that calculated in the first point?

I managed to calculate(intuitively) a tension of ##30.0V## per resistor, with basic procedures.

However, I'm finding difficulties in solving the second point.

What does the "bottom scale" mean? Isn't it simply the maximum tension that can be measured by this tool? Also, how should I use the "maximum current range" data?

Lastly: If the voltmeter must be precise, how could this result be different from that calculated in the first point?