AC generator

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

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

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 voltage induced in a conductor is ___________ ___________ to the rate which the conductor cuts the magnetic lines of force.

• inversely proportional

• directly proportional

• negatively coorelated

• absolutely opposite

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

• a conductor

• a magnetic field

• relative motion

• all three

How is contact between the coil and circuit maintained in an AC generator?

• A split ring commutator connects to each side for half a turn

• It cannot be maintained.

• The alternator can only complete one revolution and must then be rotated in reverse

• Slip rings and brushes allow continuous connection

A coil is rotated steadily between the poles of a magnet. The coil is connected to an oscilloscope.

Which graph shows the output voltage V against time t?

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Which diagram represents the voltage output of a simple a.c. generator?

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In A.C generator,by increasing the no. of turns in the coil,

• Decrease the Electromotive force (EMF)

• Electromotive force (EMF) remains the same

• Increases the Electromotive force (EMF)

• Electromotive force (EMF) becomes zero

If the coil is placed perpendicular to field lines then the number of lines passing through the coil is:

• Minimum

• Maximum

• Zero

• May be maximum or minimum

AC generator converts:

• Mechanical energy to electrical energy

• Electrical energy to mechanical energy

• Heat energy to mechanical energy

• Chemical energy to electrical energy