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Question
Copy the given diagram of a transformer and complete it. Name the parts A and B. Name the part you have drawn to complete the diagram. What is the material of this part? Is this transformer a step-up or step-down? Give reason.
Solution
The completed diagram is given below:
Part A is called primary coil. Part B is called a secondary coil.
The part drawn is called core.
The material of the core is soft iron.
(i) This transformer is step-down since it has more turns in the primary coil than in secondary coil.
(ii) A step-up transformer has more turns in secondary coil as compared to that in the primary coil, while a step-down transformer has more turns in primary coil as compared to that in secondary coil.
(iii) In a step-up transformer the wire in the primary coil is thicker as compared to that in secondary coil, while in a step-down transformer the wire in secondary coil is thicker as compared to that in primary coil.
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