ECA 1

The reciprocal of resistance is:

• Coloumbs

• Henry

• Conducatance

• Impedance

The current Io in Fig. below is:

• 4A

• 3A

• 2A

• 1A

In a Y-Y system, a line voltage of 220 V produces a phase voltage of

• 127

• 156

• 311

• 381

In a Delta - Delta system, a phase voltage of 100 V produces a line voltage of:

• 71

• 58

• 100

• 141

The instrument for measuring average power is the:

• Voltmeter

• Wattmeter

• Ammeter

• Varmeter

In the power triangle shown in Fig., the reactive power is:

• 1000 VAR Leading

• 866 VAR Leading

• 1000 VAR Lagging

• 866 VAR Lagging

A parallel RLC circuit has L = 2 H and C = 0.25 F. The value of R that will produce unity damping factor is ___ Ohm

• 0.5

• 1

• 2

• 4

In the circuit of Fig., v(∞) is:

• 10V

• 6V

• 0V

• 5V

The time constant for an RL circuit with R = 2 Ohms and L = 4 H is:

• 0.5S

• 2S

• 4S

• 6S

If the current through a 10-mH inductor increases from zero to 2 A, how much energy is stored in the inductor?

• 40mJ

• 20mJ

• 10mJ

• 60mJ