(a) Define permeability. (b) Define MMF. (c) Define form factor of an alternating quantity. (d) Define frequency and time period of an alternating quality. (e) Define transformation ratio of transformer. (f) State the EMF equation of a 1 transformer and state the meaning of each term used. (g) Give two applications of single phase motors.

(a) Define permeability. (b) Define MMF. (c) Define form factor of an alternating quantity. (d) Define frequency and time period of an alternating quality. (e) Define transformation ratio of transformer. (f) State the EMF equation of a 1 transformer and state the meaning of each term used. (g) Give two applications of single phase motors. 
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1 Answer

Answer :

Permeability : It is the ability of a magnetic/Non magnetic material to allow setting up of flux in it. 


MMF : The magneto motive force (MMF) is the force required to setup flux in a magnetic /Non magnetic material. 


Form Factor (kf) : Form Factor is defined as the ratio of RMS value of an a.c. to its average value 


Frequency : Frequency is defined as the number of cycles per second of an a.c. wave. 


Time Period : Time Period is defined as the time required to complete one cycle of an a.c. wave. 


Transformation Ratio (k) : Transformation Ratio is defined as the ratio of primary voltage to secondary voltage OR The ratio of primary number of turns to secondary number of turns or OR The ratio of secondary current to primary current. 




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applications of single phase motors : Water pumps, ceiling fan, lathe machine

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