MEXLE Nuggets

You've loaded an old revision of the document! If you save it, you will create a new version with this data.

==== Resistance measurement ====
 
Procedure for resistance measurement:
  * Set the measuring device to resistance measurement 
  * Connect the resistance to be measured to the corresponding sockets on the measuring device (the measuring device sockets labeled COM and $\Omega$
  * Read the measured value

There are different types of resistance measurement: 
  * **direct** resistance measurement 
  * **indirect** resistance measurement

\\
=== Direct resistance measurement ===
\\
Determine the nominal and measured values of the resistance for $R_{\rm 1}$ (brown, green, orange), $R_{\rm 2}$ (yellow, violet, red), $R_{\rm 3}$ (red, violet, red) and the incandescent lamp $R_{\rm L}$. Also measure the approximate resistance $R_{\rm K}$ of your body from your right to your left hand.

{{drawio>Table-1_V2.png}}
<tabcaption Table-1_V2 | Direct resistance measurement> </tabcaption>    
\\

How do you explain the deviation between $R_{\rm L,nominal}$ and $R_{\rm L,meas}$?
<wrap onlyprint> \\ \\ \\ \\  </wrap>\\
\\
\\
What consequences can $R_{\rm K}$ have?
<wrap onlyprint> \\ \\ \\ \\  </wrap>\\
\\
\\
Now determine the series and parallel connections of resistors $R_{\rm 1}$, $R_{\rm 2}$ and $R_{\rm 3}$. \\
Specify the formulas used: \\

$R_{\rm serial}$ =  \\
<wrap onlyprint> \\ \\  </wrap> \\
$R_{\rm parallel}$ (= $R_{\rm a}$ || $R_{\rm b}$) =
<wrap onlyprint> \\ \\  </wrap> \\

{{drawio>Table-2_V1-Serial+parallel.png}}
<tabcaption Table-2_V1 | Series and parallel connections> </tabcaption> 
\\
\\
=== Indirect resistance measurement ===
\\
The resistances can also be determined by measuring the current/voltage.

**Ohm's law: In an electrical circuit, the current increases with increasing voltage and decreases with increasing resistance.** \\ 
\[ I=\frac{U}{R} \]

Build the measuring circuit shown in <imgref Fig-1_V1> for each of the three resistors and set the voltage on the power supply to $~{\rm 12} ~{ V}$.

{{drawio>Fig-1_V1-indirect-measurement.png}}
<imgcaption Fig-1_V1 | Indirect resistance measurement> </imgcaption>

Measure $U_{\rm n}$ [V] and $I_{\rm n}$ [mA]. Calculate $R_{\rm n}$ [k$\Omega$] from these values.

{{drawio>Table-3_V1-indirect-measurement.png}}
<tabcaption Table-3_V1 | Indirect resistance measurement> </tabcaption>

Edit summary

Note: By editing this page you agree to license your content under the following license: CC Attribution-Share Alike 4.0 International