Licensed Electrical Contractor Electrical Theory & Fundamentals 2

Question 1

What happens to the total resistance when resistors are connected in parallel?

Accepted Answer

It is always less than the smallest resistor

Answer

It increases beyond the largest resistor

Answer

It equals the sum of all resistors

Answer

It equals the average of all resistors

Question 2

A conductor has a resistance of 10 ohms at 20°C. If the temperature increases, what happens to its resistance?

Accepted Answer

Increases, because higher temperature increases atomic vibration

Answer

Decreases, because heat reduces electron collision

Answer

Remains the same, temperature has no effect

Answer

Decreases to zero at high temperatures

Question 3

What is the unit of electrical capacitance?

Accepted Answer

Farad

Answer

Henry

Answer

Ohm

Answer

Weber

Question 4

In an AC circuit, what does the term 'reactance' refer to?

Accepted Answer

Opposition to current flow by inductors or capacitors

Answer

Resistance caused by conductor material

Answer

Power dissipated as heat

Answer

Voltage drop across a resistor

Question 5

What is the relationship between frequency and inductive reactance (XL)?

Accepted Answer

XL increases as frequency increases

Answer

XL decreases as frequency increases

Answer

XL is unaffected by frequency

Answer

XL equals frequency divided by inductance

Question 6

Two 100-ohm resistors are connected in parallel. What is the total resistance?

Accepted Answer

50 ohms

Answer

200 ohms

Answer

100 ohms

Answer

25 ohms

Question 7

What is the power factor in a purely resistive AC circuit?

Accepted Answer

1.0

Answer

0

Answer

0.5

Answer

Varies with voltage