How to Measure Potential Difference Across Series-Connected Batteries?

AI Thread Summary
To measure the potential difference across two series-connected batteries, connect the negative end of one battery to the positive end of the other, creating a combined voltage. The potential difference can be calculated using the equation ΔV = -∫^b_a E · dL, but practical measurement is straightforward. Using a voltmeter, place the leads across the terminals of the batteries to obtain a direct reading of the voltage. The physical size of the batteries does not affect their potential difference, which is determined by their chemistry. Therefore, simply measure the voltage with a voltmeter for accurate results.
Lee33
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Homework Statement



How can I measure the potential difference across two batteries? For example, if I put the batteries end to end, so the negative end of one touches the positive end of the other. And let's say both batteries have 3 volts and let's denote point A to B as the point from one battery to the other.

Homework Equations



##\Delta V = -\int^b_a\vec{E} \dot\ \vec{dL}##

The Attempt at a Solution



So if the length of both batteries is 5 cm then do I put a point C in the middle of the two batteries and measure the potential difference separately from point A to point C then from point C to point A?
 
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Lee33 said:

Homework Statement



How can I measure the potential difference across two batteries? For example, if I put the batteries end to end, so the negative end of one touches the positive end of the other. And let's say both batteries have 3 volts and let's denote point A to B as the point from one battery to the other.

Homework Equations



##\Delta V = -\int^b_a\vec{E} \dot\ \vec{dL}##

The Attempt at a Solution



So if the length of both batteries is 5 cm then do I put a point C in the middle of the two batteries and measure the potential difference separately from point A to point C then from point C to point A?

Physical size (length) is pretty much unrelated to the potential difference across a battery. Cell potential depends upon the chemistry, while current capability and capacity scale with the volume of the cell.

Take a look at the Wikipedia entry on battery sizes.

"Measure" implies a physical process of determining potential difference. In that case one simply takes a handy voltmeter, places its leads across the desired locations, and takes the reading.
 
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