Ohm's Law vs Ohmmeter: Comparing Resistance Values

In summary, both ohmmeters and Ohm's law can be used to calculate resistance values. However, Ohm's law is more accurate than ohmmeters when it comes to directly measuring current values.
  • #1
surfer
6
0
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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  • #2
Measured values should agree with theory up to the measurement errors.
 
  • #3
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?
 
  • #4
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.
 
  • #5
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.
 
  • #6
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.
 
  • #7
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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FAQ: Ohm's Law vs Ohmmeter: Comparing Resistance Values

How is Ohm's Law different from using an ohmmeter to measure resistance?

Ohm's Law is a mathematical equation that describes the relationship between voltage, current, and resistance. It states that resistance is equal to the ratio of voltage and current. On the other hand, an ohmmeter is a device used to directly measure the resistance of a circuit component. While Ohm's Law is a theoretical concept, an ohmmeter provides a practical measurement of resistance.

Which method is more accurate in determining resistance: Ohm's Law or using an ohmmeter?

Both methods can provide accurate measurements of resistance. However, using an ohmmeter is generally considered more accurate since it directly measures the resistance of a component, while Ohm's Law relies on the accuracy of voltage and current measurements.

Can Ohm's Law be used to measure resistance in all types of circuits?

Yes, Ohm's Law can be used to calculate the resistance in any circuit as long as the voltage and current values are known. However, an ohmmeter may be necessary for more complex circuits or when precise resistance measurements are needed.

Are there any limitations to using an ohmmeter to measure resistance?

Yes, there are some limitations to using an ohmmeter. For example, an ohmmeter cannot accurately measure resistance in circuits with AC current or in circuits with non-linear components such as diodes or transistors. In these cases, Ohm's Law may be a more suitable method for calculating resistance.

Can Ohm's Law and an ohmmeter be used interchangeably to measure resistance?

No, Ohm's Law and an ohmmeter are two different methods of determining resistance and should not be used interchangeably. While both methods can provide accurate measurements, they have their own limitations and are used in different situations. It is important to understand the differences between the two and use the appropriate method for the specific circuit being analyzed.

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