Why doesn't the voltage change in a parallel circuit?
2 Answers
In a parallel circuit, all components are connected across the same voltage source, meaning each component experiences the same voltage. This is because the voltage across any two points in a parallel circuit is equal, so when resistors or other components are connected in parallel, they each receive the full voltage of the power supply.
This is in contrast to a series circuit, where the voltage is divided among the components, depending on their resistances. In summary, the reason the voltage doesn't change in a parallel circuit is that each branch of the circuit has direct access to the voltage source, maintaining a consistent voltage across each component.
This is in contrast to a series circuit, where the voltage is divided among the components, depending on their resistances. In summary, the reason the voltage doesn't change in a parallel circuit is that each branch of the circuit has direct access to the voltage source, maintaining a consistent voltage across each component.
In a parallel circuit, the voltage across each component is the same because of the nature of parallel connections. To understand why this is the case, let’s delve into some fundamental concepts:
### Basic Concept of Parallel Circuits
1. **Parallel Connection**: In a parallel circuit, all the components (resistors, capacitors, etc.) are connected across the same two points. This means that each component has the same potential difference (voltage) applied across it.
2. **Voltage Distribution**: When components are connected in parallel, they share the same voltage source. Therefore, the voltage across each component is equal to the voltage of the source.
### Detailed Explanation
- **Common Voltage Source**: In a parallel circuit, the positive terminal of the voltage source is connected to one end of all the parallel components, and the negative terminal is connected to the other end. This arrangement ensures that each component experiences the same potential difference, which is equal to the voltage of the source.
- **Kirchhoff’s Voltage Law**: According to Kirchhoff’s Voltage Law, the sum of the potential differences (voltages) around any closed loop in a circuit is zero. In a parallel circuit, each component is effectively in its own loop with the source, so the voltage across each component must be equal to the voltage of the source to satisfy this law.
- **Ohm’s Law**: For resistors connected in parallel, Ohm’s Law (V = IR) implies that the voltage across each resistor is the same as the source voltage because the same current flows through each resistor as if they were connected directly across the source.
### Example for Clarity
Imagine a parallel circuit with a 12V battery and two resistors (R1 and R2) connected in parallel:
- **Voltage Across R1 and R2**: Both resistors experience the full voltage of the battery, which is 12V. This is because they are connected directly across the battery’s terminals.
- **Current Through Each Resistor**: The current through each resistor will be different based on its resistance value (I1 = V/R1 and I2 = V/R2), but the voltage across each resistor remains the same at 12V.
### Summary
In a parallel circuit, the voltage remains unchanged across all components because they are all connected directly to the same voltage source. This constant voltage is a defining feature of parallel connections, in contrast to series circuits where the voltage is divided among the components.
### Basic Concept of Parallel Circuits
1. **Parallel Connection**: In a parallel circuit, all the components (resistors, capacitors, etc.) are connected across the same two points. This means that each component has the same potential difference (voltage) applied across it.
2. **Voltage Distribution**: When components are connected in parallel, they share the same voltage source. Therefore, the voltage across each component is equal to the voltage of the source.
### Detailed Explanation
- **Common Voltage Source**: In a parallel circuit, the positive terminal of the voltage source is connected to one end of all the parallel components, and the negative terminal is connected to the other end. This arrangement ensures that each component experiences the same potential difference, which is equal to the voltage of the source.
- **Kirchhoff’s Voltage Law**: According to Kirchhoff’s Voltage Law, the sum of the potential differences (voltages) around any closed loop in a circuit is zero. In a parallel circuit, each component is effectively in its own loop with the source, so the voltage across each component must be equal to the voltage of the source to satisfy this law.
- **Ohm’s Law**: For resistors connected in parallel, Ohm’s Law (V = IR) implies that the voltage across each resistor is the same as the source voltage because the same current flows through each resistor as if they were connected directly across the source.
### Example for Clarity
Imagine a parallel circuit with a 12V battery and two resistors (R1 and R2) connected in parallel:
- **Voltage Across R1 and R2**: Both resistors experience the full voltage of the battery, which is 12V. This is because they are connected directly across the battery’s terminals.
- **Current Through Each Resistor**: The current through each resistor will be different based on its resistance value (I1 = V/R1 and I2 = V/R2), but the voltage across each resistor remains the same at 12V.
### Summary
In a parallel circuit, the voltage remains unchanged across all components because they are all connected directly to the same voltage source. This constant voltage is a defining feature of parallel connections, in contrast to series circuits where the voltage is divided among the components.