Question

1. a parallel branch that has a changed value component________.a allows no currentb changes ( z_t ), ( i_t ), and voltage dropsc eliminates the effect of the changed value componentd measures the applied voltage across the changed value component

Explanation:

In a parallel circuit, the total impedance \(Z_T\) is calculated using \(\frac{1}{Z_T}=\sum\frac{1}{Z_i}\). If a component's value (impedance \(Z_i\)) changes, \(Z_T\) changes. According to Ohm's law \(I = \frac{V}{Z}\), since \(Z_T\) changes and the source voltage \(V\) is constant (in a simple parallel - source circuit), the total current \(I_T=\frac{V}{Z_T}\) changes. Also, in a parallel circuit, the voltage across each branch is the same as the source voltage (assuming ideal source and no other series - connected non - parallel elements). But if we consider a more complex circuit with some series elements (e.g., a source with internal impedance in series with the parallel branches), a change in a parallel - branch component can affect the voltage division.

• Option a: In a parallel circuit, even if a component value changes (as long as it's not an open - circuit), current will flow through the other branches. So, this option is incorrect.
• Option b: As explained above, a change in a parallel - branch component value changes \(Z_T\) (using the parallel - impedance formula \(\frac{1}{Z_T}=\sum\frac{1}{Z_i}\)), then \(I_T=\frac{V}{Z_T}\) (by Ohm's law) changes. And in a non - ideal source (or a circuit with series elements with the parallel branches), voltage drops (e.g., across a source's internal resistance) can change. This option is correct.
• Option c: A change in a parallel - branch component value does not eliminate its own effect. For example, if a resistor value in a parallel branch changes, it affects the total current and impedance. So, this option is incorrect.
• Option d: A parallel branch with a changed - value component does not measure voltage. Measuring voltage requires a voltmeter. This option is incorrect.

Answer:

b. changes \(Z_T\), \(I_T\), and voltage drops