Proving Ohm's Law between 2 circuits

In summary, the speaker is asking for help with a physics lab assignment involving proving Ohm's law. They are having trouble with two different circuits giving different results and are unsure of the reason why. They mention that the units for current are measured in amperes and suspect that the equipment may be faulty.
  • #1
superjose
15
0

Homework Statement


Hello guys. I've ran into this conceptual problem. I was given into physic's lab to prove Ohm's law by mounting a circuit in two ways, and calculate both Voltage and Intensity.


The first circuit, the A (Please refer to Circuit A.jpg), has the inconvenient in which the ammeter does not measure the current (I) which passes through the resistance *(R), but the total intensity (I) of the circuit.

The second one, the B (Please refer to Circuit B.jpg), has the inconvenient in which the voltmeter does not really measure the potential difference between the ends of the resistance, but between the ends of the association of resistance in series with the ammeter:


They should give me the same. Problem is, the results between circuit A and circuit B gave me different, and I must know why. The teacher said something about the resistance, but it didn't quite grasp what he said. I'm recurring here for help, any ideas?


Thanks a lot in advance.

P.S.: I've left you the results from Circuit A and B. They both were done by making the Voltage as the independent variable.



Homework Equations



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The Attempt at a Solution


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Attachments

  • Circuit A.jpg
    Circuit A.jpg
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  • Circuit B.jpg
    Circuit B.jpg
    7.1 KB · Views: 460
  • Circuit A and BResults.PNG
    Circuit A and BResults.PNG
    12 KB · Views: 505
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  • #2
what are your units for current? A, mA, uA, nA?

most of the time I would say that has something to do with the finite resistance values of you voltmeter and ammeter, but if your current values are measured in whole amperes then you probably have other problems as well, or your equipments are particularly lousy...
 
  • #3
Thanks for the quick reply.

Sorry for not posting the units! But yest, they are measured in Ampere (A).

Being the lousy equipment could be a very big possibility, since I don't believe they are taken good care of them.
 

1. What is Ohm's Law?

Ohm's Law is a fundamental law in physics that describes the relationship between voltage, current, and resistance in an electrical circuit. It states that the current through a conductor between two points is directly proportional to the voltage across the two points, and inversely proportional to the resistance between them.

2. How do you prove Ohm's Law between 2 circuits?

To prove Ohm's Law between 2 circuits, you will need to measure the voltage and current in each circuit and then compare the results. This can be done by using a voltmeter to measure the voltage and an ammeter to measure the current. By comparing the values of voltage and current in each circuit, you can determine if they follow the relationship described by Ohm's Law.

3. What equipment is needed to prove Ohm's Law?

To prove Ohm's Law, you will need a power source, resistors of known values, voltmeter, and ammeter. You may also need a multimeter, which combines the functions of a voltmeter and ammeter in one device. It is important to use high-quality and accurate equipment to ensure accurate measurements.

4. What are the limitations of Ohm's Law?

Ohm's Law is a fundamental law in physics, but it does have some limitations. It is only applicable to linear circuits, meaning that the voltage and current must vary in direct proportion to each other. It also assumes that the temperature and other environmental factors remain constant. Additionally, Ohm's Law only applies to materials that have a constant resistance, such as resistors.

5. How is Ohm's Law used in real-world applications?

Ohm's Law is used in a variety of real-world applications, including designing and analyzing electrical circuits, calculating power and energy usage, and troubleshooting electrical problems. It is also used in industries such as electronics, telecommunications, and power generation and distribution. Understanding Ohm's Law is essential for anyone working with electricity or designing electrical systems.

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