Question

evaluation and review questions: 1. compare the voltage difference calculation in tables 8 - 3 through table 8 - 6. does the circuits reference point have any effect on the voltage - differences across any of the resistors? explain your answer. 2. define the term reference ground.

Explanation:

1. Voltage difference is the potential difference between two points. The reference point is an arbitrarily chosen point with zero - potential. Changing the reference point does not change the actual potential difference across resistors because potential difference is a relative quantity between two points in the circuit. For example, if we have points A, B and change the zero - potential reference from one point to another, the voltage $V_{AB}=V_A - V_B$ remains the same.
2. Reference ground is a common electrical point in a circuit that is assigned a potential of zero volts. It serves as a common return path for current and a reference for all other voltage measurements in the circuit. It can be connected to the earth in some cases (such as in building electrical systems) or just be an internal common point in a circuit like in an electronic device.

Answer:

1. The circuit's reference point has no effect on the voltage differences across any of the resistors. This is because voltage difference is a relative quantity between two points in the circuit and changing the zero - potential reference does not change the actual potential difference between those two points across the resistors.
2. Reference ground is a common electrical point in a circuit that is assigned a potential of zero volts. It is used as a reference for all other voltage measurements in the circuit and can serve as a common return path for current.