Unterschiede

Hier werden die Unterschiede zwischen zwei Versionen angezeigt.

Link zu dieser Vergleichsansicht

Beide Seiten der vorigen Revision Vorhergehende Überarbeitung
Nächste Überarbeitung		 Vorhergehende Überarbeitung
electrical_engineering_1:aufgabe_2.7.8_mit_rechnung [2022/05/05 08:12] – tfischerelectrical_engineering_1:aufgabe_2.7.8_mit_rechnung [2023/03/19 19:04] (aktuell) – mexleadmin
Zeile 6: Zeile 6:
  
 Given is the adjoining circuit with \\ Given is the adjoining circuit with \\
-$R_1=5 \Omega$\\ +$R_1=5 ~\Omega$\\ 
-$R_2=10 \Omega$\\ +$R_2=10 ~\Omega$\\ 
-$R_3=20 \Omega$\\+$R_3=20 ~\Omega$\\
  
-1. determine the equivalent resistance $R_{eq}$ between A and B by summing the resistances.+1. Determine the equivalent resistance $R_{\rm eq}$ between A and B by summing the resistances.
  
 <button size="xs" type="link" collapse="Solution_2_7_8_1_Tips">{{icon>eye}} Tips for solving</button><collapse id="Solution_2_7_8_1_Tips" collapsed="true"> <button size="xs" type="link" collapse="Solution_2_7_8_1_Tips">{{icon>eye}} Tips for solving</button><collapse id="Solution_2_7_8_1_Tips" collapsed="true">
   * How can the circuit be better represented or pulled apart?   * How can the circuit be better represented or pulled apart?
-  * Switches (when used) should be replaced by an open of closed circuit.+  * Switches (when used) should be replaced by an open or closed circuit.
   * Does this result in equal potentials at different nodes that can be cleverly used?   * Does this result in equal potentials at different nodes that can be cleverly used?
 </collapse> </collapse>
Zeile 28: Zeile 28:
 {{elektrotechnik_1:schaltung_klws2020_2_2_1_loesung2.jpg?300}} {{elektrotechnik_1:schaltung_klws2020_2_2_1_loesung2.jpg?300}}
  
-Here it helps to consider the potential of the nodes K1, K2 and K3. For K2, the resistances $R_2 || R_3 || R_2$ must be combined at the top and bottom. Thus, the same resistance values at the top and bottom result. Also at the nodes K1 and K2 the same resistance values at the top and at the bottom result. With the same ratios of the resistances at K1, K2 and K3 respectively, it can be concluded that no current flows across the resistors $R_3$ between K1 and K2 or K2 and K3. Thus, these do not contribute to the total resistance. In such a case, a short circuit or an open line can be freely chosen between the relevant nodes for the calculation. In the following an open line is chosen. Additionally the parallel strings can be reordered. \\+Here it helps to consider the potential of the nodes K1, K2, and K3. For K2, the resistances $R_2 || R_3 || R_2$ must be combined at the top and bottom. Thus, the same resistance values at the top and bottom result. Also at the nodes K1 and K2 the same resistance values at the top and at the bottom result. With the same ratios of the resistances at K1, K2, and K3 respectively, it can be concluded that no current flows across the resistors $R_3$ between K1 and K2 or K2 and K3. Thus, these do not contribute to the total resistance. In such a case, a short circuit or an open line can be freely chosen between the relevant nodes for the calculation. In the following, an open line is chosen. Additionally, the parallel strings can be reordered. \\
  
 <WRAP> <WRAP>
Zeile 41: Zeile 41:
  
 \begin{align*} \begin{align*}
-R_{ges} &= \left( \left( 2 \cdot R_2 \right) || \left( 2 \cdot R_2 \right) \right) && || \; \left( \left( 2 \cdot R_3 \right) || \left( 2 \cdot R_3 \right) || \left( 2 \cdot R_3 \right) \right)  \\ +R_{\rm eq} &= \left( \left( 2 \cdot R_2 \right) || \left( 2 \cdot R_2 \right) \right) && || \; \left( \left( 2 \cdot R_3 \right) || \left( 2 \cdot R_3 \right) || \left( 2 \cdot R_3 \right) \right)  \\ 
-R_{ges} &= R_2 && || \;\left( R_3 || \left( 2 \cdot R_3 \right) \right)  \\ +R_{\rm eq} &= R_2 && || \;\left( R_3 || \left( 2 \cdot R_3 \right) \right)  \\ 
-R_{ges} &= R_2 && || \;\frac{R_3 \cdot 2 R_3}{R_3 + 2 R_3}   \\ +R_{\rm eq} &= R_2 && || \;\frac{R_3 \cdot 2 R_3}{R_3 + 2 R_3}   \\ 
-R_{ges} &= R_2 && || \;\frac{2}{3}\cdot R_3 \\ +R_{\rm eq} &= R_2 && || \;\frac{2}{3}\cdot R_3 \\ 
-R_{ges} &=  \frac{R_2 \cdot \frac{2}{3}\cdot R_3}{R_2 + \frac{2}{3}\cdot R_3} \\ +R_{\rm eq} &=  \frac{R_2 \cdot \frac{2}{3}\cdot R_3}{R_2 + \frac{2}{3}\cdot R_3} \\ 
-R_{ges} &=  \frac{R_2 \cdot R_3}{\frac{3}{2}\cdot R_2 + R_3}+R_{\rm eq} &=  \frac{R_2 \cdot R_3}{\frac{3}{2}\cdot R_2 + R_3}
    \\ \\    \\ \\
 \end{align*} \end{align*}
Zeile 54: Zeile 54:
 <button size="xs" type="link" collapse="Solution_2_7_8_1_Final_result">{{icon>eye}} Final result</button><collapse id="Solution_2_7_8_1_Final_result" collapsed="true"> <button size="xs" type="link" collapse="Solution_2_7_8_1_Final_result">{{icon>eye}} Final result</button><collapse id="Solution_2_7_8_1_Final_result" collapsed="true">
 \begin{align*} \begin{align*}
-R_{ges} &= \frac{10 \Omega \cdot 20 \Omega}{\frac{3}{2}\cdot 10 \Omega + 20 \Omega} = 5.7143 \Omega -> 5.7 \Omega +R_{\rm eq} &= \frac{10 ~\Omega \cdot 20 ~\Omega}{\frac{3}{2}\cdot 10 ~\Omega + 20 ~\Omega} = 5.7143 ~\Omega \rightarrow 5.7 ~\Omega 
 \end{align*} \end{align*}
  \\  \\
 </collapse> </collapse>
  
-2. now let the voltage from A to B be: $U_{AB}=U_0= 20 V$. What is the current $I$?+2. Now let the voltage from A to B be: $U_{AB}=U_0= 20 ~\rm V$. What is the current $I$?
  
 <button size="xs" type="link" collapse="Solution_2_7_8_2_Solution_Path">{{icon>eye}} Solution</button><collapse id="Solution_2_7_8_2_Solution_Path" collapsed="true"> <button size="xs" type="link" collapse="Solution_2_7_8_2_Solution_Path">{{icon>eye}} Solution</button><collapse id="Solution_2_7_8_2_Solution_Path" collapsed="true">
Zeile 71: Zeile 71:
 <button size="xs" type="link" collapse="Solution_2_7_8_2_Final_result">{{icon>eye}} Final result</button><collapse id="Solution_2_7_8_2_Final_result" collapsed="true"> <button size="xs" type="link" collapse="Solution_2_7_8_2_Final_result">{{icon>eye}} Final result</button><collapse id="Solution_2_7_8_2_Final_result" collapsed="true">
 \begin{align*} \begin{align*}
-I =\frac{20V}{2 \cdot 20 \Omega} = 0.5 A+I =\frac{20~V}{2 \cdot 20 ~\Omega} = 0.5 ~\rm A
 \end{align*} \end{align*}
  \\  \\