Question

The impedance vector, in a vector-impedance diagram, is parallel to $x$-axis. The circuit is:

Answer 1

Explanation

1. The impedance vector from a vector-impedance diagram is always parallel to $x$-axis
2. The circuit is entirely resistive.
3. In parallel $\mathrm{RLC}$circuit that contains a resistor, an inductor, and a capacitor the circuit current $\mathrm{IS}$ is the phasor addition consisting of three components ${\mathrm{I}}_{\mathrm{R}},{\mathrm{I}}_{\mathrm{L}}$ and ${\mathrm{I}}_{\mathrm{C}}$ with the supply voltage common to all three.
4. As the supply voltage is common to all three components, it is used as the horizontal reference while constructing a current triangle
5. 
6. Parallel $\mathrm{RLC}$ network can be observed by vector diagram just like series $\mathrm{RLC}$ circuits.
7. But the analysis of parallel $\mathrm{RLC}$circuits is mathematically hard for series $\mathrm{RLC}$ circuits when it contains two or more current divisions.
8. So, an $\mathrm{AC}$ parallel circuit can be simply evaluated by using the reciprocal of impedance.
9. 
10. 

Note :Admission is the inverse of impedance indicated by the symbol $Y$. Impedance is a complicated quantity that has both a real and an imaginary component. The real portion is the reciprocal of resistance and is denoted by the symbol $Y$, Conductance, whereas the imaginary portion is the reciprocal of reactance and is denoted by Susceptance.

Hence, the circuit is purely resistive.