Inductance

Inductance is measured in _____

• reactance

• ohms

• hertz

• henrys

An inductor has an inductance of 1.4H and is connected to a 60-Hz supply. What is the inductive Reactance?          

• 621.59 Ω

• 600 Ω

• 527.79 Ω

• 500 Ω

Which of the following formulas should be used to find total inductance in a purely inductive series circuit?

• LT = L1+L2+L3

• LT = 1/(1/L1+1/L2+1/L3)

• LT = L1 = L2 = L3

• LT = √(L1²+L2²)

True power can only be produced when voltage and current share the same polarity 50% of the wave cycle.

• True

• False

Which of the following formulas should be used to find total voltage in a purely inductive parallel circuit?

• ET = EL1+EL2+EL3

• ET = 1/(1/EL1+1/EL2+1/EL3)

• ET = EL1 = EL2 = EL3

• ET = √(EL1²+EL2²)

An inductor has an XL of 40 Ω is connected to a 60-Hz supply. What is the inductance?          

• .590

• .758H

• .106H

• .213H

An inductor ___________ a change of current      

• attracts

• resists

• powers

• opposes

In a purely inductive circuit, the voltage _____

• lags current by 90°

• leads current by 90°

• is in phase with current

• is out of phase with current by 180°

An inductor has an internal wire resistance of 20Ω and an inductive reactance of 220Ω. What is the quality(Q) of the inductor?

• 9

• 10

• 11

• 12

The unit of measure for reactive power of an inductor is _____.

• VA

• joules

• VARs

• watts