- #1
jegues
- 1,097
- 3
So, your final solution is correct except for a wrong sign on V2.
jegues said:Why is V2 negative?
Zryn said:The voltage (difference in potential) dropped across a resistor is equal to the higher potential minus the lower potential divided by the resistance.
The Electrician said:If you're calculating the currents leaving a node, call it Vx, then if a resistor is connected to another node, Vz perhaps, the resistor current is (Vx-Vz)/R. If the resistor is connected to ground then Vz is automatically zero, so the current is (Vx-0)/R = Vx/R.
Zryn said:Your fraction is incorrect. Keep in mind voltages in series add together.
What is the voltage on the left of the Resistor??
What is the voltage on the right of the Resistor?
Not every component is a voltage immediately in series with another voltage however.
Zryn said:Exactly!
Now you should be able to conquer most voltage dividers easily ;).
A node voltage is the potential difference between two nodes in an electrical circuit. It is measured in volts (V) and is used to analyze the behavior of a circuit.
To solve a node voltage question, you need to first identify all the nodes in the circuit and assign them a reference node. Then, use Kirchhoff's Current Law (KCL) and Kirchhoff's Voltage Law (KVL) to write equations for each node. Finally, use algebraic techniques to solve for the unknown node voltages.
Kirchhoff's Current Law (KCL) states that the sum of currents entering a node must be equal to the sum of currents leaving that node. This law is based on the principle of conservation of charge in a circuit.
Kirchhoff's Voltage Law (KVL) states that the sum of voltage drops in a closed loop must be equal to the sum of voltage rises in that loop. This law is based on the principle of conservation of energy in a circuit.
No, Ohm's Law only applies to simple circuits with resistors in series or parallel. Node voltage questions involve more complex circuits with multiple nodes and sources, so Ohm's Law cannot be used to solve them.