CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

Draw a labelled diagram of a step-up transformer and explain how does it work. State two characteristics of the primary coil as compared to its secondary coil.


Solution

selina-icse-solutions-class-10-physics-electro-magnetism-10c-31
 

Step-up transformer: The step-up transformer is used to change a low voltage alternating e.m.f. to a high voltage alternating e.m.f. of same frequency.

Working: When the terminals of the primary coil are connected to the source of an alternating e.m.f., a varying current flows through it which also produces a varying magnetic field in the core of the transformer. Thus, the magnetic field lines linked with the secondary coil vary and induce an e.m.f. in the secondary coil. The induced e.m.f. varies in the same manner as the applied e.m.f. in the primary coil varies, and thus, has the same frequency as that of the applied e.m.f.
The magnitude of e.m.f. induced in the secondary coil depends on the ‘turns ratio’ and the magnitude of the applied e.m.f.
For a transformer,
fraction numerator E. m. f space a c r o s s space t h e space s e c o n d a r y space c o i l space left parenthesis E subscript s right parenthesis over denominator E m f space a c r o s s space t h e space p r i m a r y space c o i l space left parenthesis E subscript P end fraction equals fraction numerator N u m b e r space o f space t u r n s space i n space t h e space s e c o n d a r y space c o i l space left parenthesis N subscript s right parenthesis over denominator N u m b e r space t u r n s space i n space t h e space p r i m a r y space c o i l space left parenthesis N subscript P right parenthesis end fraction

Two characteristics of the primary coil as compared to its secondary coil:

  1. The number of turns in the primary coil is less than the number of turns in the secondary coil.
  2. A thicker wire is used in the primary coil as compared to that in the secondary coil.

flag
 Suggest corrections
thumbs-up
 
0 Upvotes


Similar questions
View More


Same exercise questions
View More


People also searched for
View More



footer-image