Ohm's Law vs Ohmmeter: Comparing Resistance Values

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SUMMARY

The discussion centers on the reliability of resistance measurements obtained from an ohmmeter compared to those calculated using Ohm's Law. It concludes that both methods should yield similar results within measurement errors, but the accuracy can vary based on the type of resistor and its tolerance levels (5%, 1%, or 0.5%). The consensus is that neither method is definitively more reliable than the other; instead, they should be used in conjunction to achieve accurate circuit values. Measurement errors and the specific characteristics of the resistors play a crucial role in determining the reliability of the readings.

PREREQUISITES
  • Understanding of Ohm's Law and its application in electrical circuits
  • Familiarity with ohmmeters and their operational principles
  • Knowledge of resistor types and tolerance levels (5%, 1%, 0.5%)
  • Basic skills in measuring voltage and current in circuits
NEXT STEPS
  • Research the operational principles of different types of ohmmeters
  • Learn about resistor color codes and how to determine resistance values
  • Study the impact of measurement errors on electrical readings
  • Explore advanced techniques for measuring current in circuits
USEFUL FOR

Electronics students, electrical engineers, and hobbyists interested in understanding resistance measurement techniques and improving accuracy in circuit analysis.

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Are the resistance values of resistors which measured by ohmmeter and Ohm's law equal each other. Which of them are realiby than other? Please help me!
 
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Measured values should agree with theory up to the measurement errors.
 
surfer said:
Are the resistance values of resistors which measured by ohmmeter and Ohm's law equal each other. Which of them are realiby than other? Please help me!

How does your ohmmeter determine a value of the resistance? How does an ohmmeter work?
 
It must be the same within the measurement errors except for the fact that you measure at the boundary values. I mean if your ohmmeter has the measuring range from 1ohm to 10megaohm and you measure a resistor of about 1 ohm or appr.10 Mohm.
It also depends on what kind of resistors you have. Some kinds of resistors have higher accuracy than others. There are resistors with 5%, 1% or 0.5% tolerance etc.
 
In fact, I asked this question in general. So i have wanted you to give a general answer to me. There is no specific ohmmeter and there is no specific resistor. I asked only which one is more reliable? And thank all of you for your interests.
 
I would not consider one more "reliable" then the other.

If you want to know what the actual circuit values are you must measure them, there are to many variables to rely solely on Ohm's law calculations.

For the standard resistor, use the color code to find it's resistance. Now with a voltage measurement and Ohm's law you can determine the current. It is usually difficult to directly measure current since you must insert the ammeter into the circuit.

Thus measurements and Ohm's law must be used together. They should not be seen as separate approaches.
 
They are the same thing surfer. You have to measure volts to come up with a voltage to plug into the formula for ohms law. You have to measure the current also. An ohmeter uses all of the same components that voltmeters and current meters use. So you tell me, which is more accurate?
 
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