Electrical Circuit Final Exam Revision

Dielectric is another name for __________

• ceramic

• capacitor

• electric charge

• insulating material in a capacitor

The basic unit of electric charge is ____________.

• ampere

• coulomb

• farad

• capacitance

The basic unit for capacitance is _____________

• farad

• coulomb

• weber

• volt

When an alternating voltage is applied across a pure resistance ____________.

• the voltage and current are out of phase with each other

• the voltage and current are in phase with each other

• the voltage leads the current by 90^o

• the voltage lags the current by 90^o

When an alternating voltage is applied across a pure inductance _________________.

• the voltage and current are in phase with each other

• the voltage leads the current by 90^o

• the voltage lags the current by 90^o

• none of the above

When the voltage and current in a circuit are  v = 100 sin Θ and i = 50 sin Θ,it means that the circuit has _____________.

• pure inductance only

• pure capacitance only

• pure resistance only

• all three components

When the voltage and current in a circuit are  v = 100 sin Θ and i = 50 sin ( Θ + 90^o ), it means that the circuit has ________________.

• pure inductance only

• pure capacitance only

• pure resistance only

• all three components

In an ac circuit, the inductive reactance is ____________

• X_L = 2 πf L

• X_L = 1 / 2 πf L

• X_L = 2 πf L²

• X_L = √2 πf L

When an alternating voltage of frequency  f  hertz is applied across a pure capacitance of  C  farads, the capacitive reactance is ____________

• X_C = R

For an ac circuit of a pure resistance R, pure inductive reactance X_L and pure capacitive reactance, X_C in series, the impedance of the circuit is _____________

• Z = √R² + (X_L – X_C)²

• Z = √R² + (X_L + X_C)²

• Z =  R² + (X_L – X_C)²

• Z =  R² + (X_L +  X_C)²