Transformer and Power Systems Quiz

What is the primary function of a transformer?

• Convert AC to DC

• Step up or step down voltage

• Increase current

• Decrease resistance

The efficiency of a transformer is typically in the range of:

• 50-60%

• 60-70%

• 70-80%

• 95-99%

In a transformer, the core is usually made of:

• Copper

• Aluminum

• Iron

• Plastic

Power factor is defined as the ratio of:

• Real power to apparent power

• Apparent power to real power

• Reactive power to apparent power

• Real power to reactive power

Which device is commonly used for power factor correction?

• Resistor

• Inductor

• Capacitor

• Transformer

Improving power factor can result in:

• Increased energy consumption

• Reduced energy bills

• Increased voltage drops

• Decreased system capacity

Commutation in a DC motor refers to:

• Changing AC to DC

• Reversing current direction

• Increasing voltage

• Decreasing resistance

A commutator is typically made of:

• Iron

• Copper

• Aluminum

• Plastic

D.O.L starter stands for:

• Direct On Line starter

• Direct Off Line starter

• Direct Over Load starter

• Direct On Load starter

A D.O.L starter is suitable for motors with power ratings up to:

• 1 kW

• 5 kW

• 10 kW

• 20 kW