Course 07001

In a purely inductive circuit, the phase angle between the voltage and the current is:

• 90 degrease

• 45 degrease

• 180 degrease

• 0 degrease

What is the formula for calculating total capacitance (CT​) in a parallel circuit?

• CT = C1 + C2 + C3

• CT = C1 - ( C2 + C3 )

• CT = 1\C1 + 1\C2 + 1\C3

What happens to the overall circuit current when a capacitive load is connected in parallel with a motor?

• Decreases

• Increases

• Stays the same

• Cancel out each other

How do you calculate the total current in a parallel RLC circuit?

• 
  Add the branch currents vectorially at their respective phase angles.

• Multiply the branch currents by their impedances.

For a motor with a lagging power factor adding a capacitor, causes the total current phasor to:

• Lag the supply voltage more.

• Have a reduced angle with the supply voltage.

• Leads the power factor

• Stays the same

A resistor (R=12 Ω) and an inductor (XL=16 Ω) are connected in series. What is the total impedance (Z)?

• 20

• 30

• 28

• 9

In a series RLC circuit, the power factor (PF) is defined as:

• PF = Z / R

• PF = R / Z

• PF = V x I

• PF = V \ I

A 100 μF capacitor is connected to a 60 Hz AC source. What is its capacitive reactance?

• 26.5

• 20

• 15

• 10

In an impedance diagram where XL > XC, what does the phase angle (θ) represent?

• The current leads the voltage

• The current lags the voltage

• The current and voltage are in phase.

• The current leads the current.

In a series RC circuit, what is the total opposition to current called?

• Resistance

• Impedance

• Voltage

• Power factor