AC GENERATOR

The direction of the induced current in the coil of a generator depends on the …

• length of the coil.

• speed of rotation of the coil.

• direction of the magnetic field.

• strength of the magnetic field.

Which ONE of the following combinations regarding the energy conversions in electric motors and electric generators is CORRECT?

• ENERGY CONVERSION IN MOTORS: Mechanical to electrical

  ENERGY CONVERSION IN GENERATORS: Electrical to mechanical

• ENERGY CONVERSION IN MOTORS: Mechanical to electrical

  ENERGY CONVERSION IN GENERATORS: Mechanical to electrical

• ENERGY CONVERSION IN MOTORS: Electrical to mechanical

  ENERGY CONVERSION IN GENERATORS: Electrical to mechanical

• ENERGY CONVERSION IN MOTORS: Electrical to mechanical

  ENERGY CONVERSION IN GENERATORS: Mechanical to electrical

Which ONE of the following actions will NOT cause an increase in the induced emf in a coil if the coil is rotated in a uniform magnetic field?

• Rotating the coil faster

• Increasing the strength of the magnetic field

• Increasing the number of turns of the coil

• Replacing the coil with a coil of lower resistance

Which ONE of the following changes may lead to an increase in the emf of an AC generator without changing its frequency?

• Decrease the resistance of the coil.

• Increase the area of the coil.

• Increase the resistance of the coil.

• Decrease the speed of rotation.

The speed of rotation of the coils in an AC generator is increased. Which ONE of the following combinations of frequency and output voltage for the generator will occur as a result of the change?

• FREQUENCY: Increases

  OUTPUT VOLTAGE: Increases

• FREQUENCY: No change

  OUTPUT VOLTAGE: Increase

• FREQUENCY: Decrease

  OUTPUT VOLTAGE: Decrease

• FREQUENCY: Increase

  OUTPUT VOLTAGE: No change

A DC generator operates at 80 Hz. The number of times the output voltage reaches a maximum in 1 second is ...

• 40

• 80

• 120

• 160

Which of these is NOT a part of a DC Generator.

• Slip rings
• commutator 
• brushes
• stator

The process of generating the current in a conductor is called as 

• Electro motive force 
• Electromagnetic induction 
• generator energy conversion 
• induced voltage

AC generators have 

• 2 slip rings 
• 1 slip ring 
• 3 slip rings 
• 4 slip rings

In order for electromagnetic induction to occur, you need...

• a conductor

• a magnetic field

• relative motion

• all three