# Online Electrical Engineering Test - Electrical Engineering Test - Random Loading Test...

Instruction:

• This is a FREE online test. DO NOT pay money to anyone to attend this test.
• Total number of questions : 20.
• Time alloted : 30 minutes.
• Each question carry 1 mark, no negative marks.
• DO NOT refresh the page.
• All the best :-).

1.

When a solenoid is activated, the force that moves the plunger is

A.
 an electromagnetic field B.
 a permanent magnetic field C.
 varying voltage D.
 a steady current 2.

What is the reluctance of a material that has a length of 0.07 m, a cross-sectional area of 0.014 m2, and a permeability of 4,500 Wb/At × m?

A.
 1111 At/Wb B.
 111 At/Wb C.
 11 At/Wb D.
 1 At/Wb 3.

How many primary volts must be applied to a transformer with a turns ratio of 0.1 to obtain a secondary voltage of 9 V?

A.
 9 V B.
 90 V C.
 900 V D.
 0.9 V Explanation:

We know that, V2/V1 = N2/N1.

Given V2 = 9v, N2/N1 = 0.1

Therefore, 9v/V1 = 0.1

V1 = 9v/0.1 = 90v.

For more detail: Step Down Transformer - Circuit with Simulation.

4.

The primary winding of a transformer has 110 V ac across it. What is the secondary voltage if the turns ratio is 8?

A.
 8.8 V B.
 88 V C.
 880 V D.
 8,800 V Explanation:

V2/V1 = N2/N1

Turns ratio = N2/N1 = 8.

V2/110 = 8

V2 = 8 x 110

V2 = 880v.

5.

The turns ratio required to match an 80 source to a 320 load is

A.
 80 B.
 20 C.
 4 D.
 2 6.

To increase the current in a series RL circuit, the frequency

A.
 should be increased B.
 should be decreased C.
 should be constant D.
 cannot be determined without values 7.

When the frequency is decreased, the impedance of a parallel RL circuit

A.
 increases B.
 decreases C.
 remains constant D.
 is not a factor 8.

Norton's theorem gives

A.
 an equivalent current source in parallel with an equivalent impedance B.
 an equivalent current source in series with an equivalent impedance C.
 an equivalent voltage source in parallel with an equivalent impedance D.
 an equivalent voltage source in series with an equivalent impedance 9.

Find the current in R2 of the given circuit, using the superposition theorem. A.
 16.7 mA B.
 33.3 mA C.
 50 mA D.
 16.6 mA 10.

An autotransformer is one in which the primary and secondary are automatically coupled.

A.
 True B.
 False 11.

In an ac circuit, power to the load peaks at the frequency at which the load impedance is the complex conjugate of the output impedance.

A.
 True B.
 False 12.

The number 4,500,000 can be expressed as

A.
 4,500 × 106 B.
 4.5 × 106 C.
 4.5 × 10-3 D.
 either 4,500 × 104 or 4.5 × 106 13.

The number of millivolts in 0.06 kilovolts is

A.
 600 V B.
 6,000 mV C.
 60,000 mV D.
 600,000 mV 14.

Polyphase is characterized by two or more sinusoidal voltages, each having a different phase angle.

A.
 True B.
 False 15.

How much current is produced by a voltage of 18 kV across a 15 k resistance?

A.
 1.2 A B.
 12 A C.
 120 mA D.
 12 mA 16.

The unit of electrical charge is the

A.
 coulomb B.
 joule C.
 volt D.
 watt 17.

When a 1.6 k resistor and a 120 resistor are connected in parallel, the total resistance is

A.
 greater than 1.6 k  B.
 greater than 120 but less than 1.6 k  C.
 less than 120 but greater than 100  D.
 less than 100  18.

The complex number 40 55° is equivalent to

A.
 55 + j55 B.
 40 + j40 C.
 45.88 + j65.52 D.
 22.94 + j32.76 19.

Using the current-divider formula, you can find the current in any branch of a series-parallel circuit.

A.
 True B.
 False 20.

The branch current method uses

A.
 Kirchhoff's voltage and current laws B.
 Thevenin's theorem and Ohm's law C.
 Kirchhoff's current law and Ohm's law D.
 the superposition theorem and Thevenin's theorem 