M3 Cat B bank

What is the value of Z in the circuit shown?

What is the value of R in the circuit shown?

Which of these statements is true if you change the voltage from 28V dc to 28V ac in a resistive circuit?

• The real power decreases

• The real power remains the same

• the apparent power increases

• the reactive power decreases

• The reactive power decreases

True or False

If the frequency of the supply increases then the capacitive reactance increases

• False

• True

Which component would increase its opposition to current flow with a decrease in frequency?

• Inductance
• Diode

• Capacitance
• Resistance

What is the cause of reactive sparking?

• The meeting of the brushes and the coils within the neutral zone

• The meeting of the brushes and the coils outside the neutral zone

• running the motor at high speeds at altitude

• Running a series motor without a load.

Where are the compensation windings in a dc machine?

• Between the main poles

• Around the Interpole

• In the armature
• In the main field winding

Which of the following power triangles is correct?

• 
• 
• 
• 

Within a soft magnetic cored transformer, which losses are associated with heat loss?

• vibration losses

• magnetic losses

• iron losses

• copper losses

• Friction losses

Which formula is correct for expressing the transformation of resistance?