Question

1. a series circuit that has a changed value component

a allows no current

b changes ( z _ { t } , i _ { t } ), and voltage drops

c eliminates the effect of the changed value component

d measures the applied voltage across the changed value component

Explanation:

In a series circuit, the total impedance \(Z_T\) is the sum of individual impedances (\(Z_T=\sum Z_i\)). According to Ohm's law \(I_T = \frac{V}{Z_T}\) (where \(V\) is the applied voltage), a change in a component's value (which changes its impedance \(Z_i\)) will change \(Z_T\). Since \(I_T=\frac{V}{Z_T}\), \(I_T\) also changes. And the voltage drop across a component \(V_i = I_T\times Z_i\), so voltage drops (\(V_i\)) across components (including the non - changed ones, because \(I_T\) changes) also change.

• Option a: A series circuit with a changed - value component (not an open - circuit component) still allows current (unless it's an open - circuit, but just a value change doesn't mean open - circuit).
• Option c: The change in the component's value affects the whole circuit (as shown by the changes in \(Z_T\), \(I_T\), and voltage drops), it doesn't eliminate its effect.
• Option d: A changed - value component in a series circuit doesn't measure voltage; measuring voltage requires a voltmeter.

Answer:

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