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MODEL PAPER 1 — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsMODEL PAPER 11 Mark
Question
Assertion (A) :A step-up transformer cannot be used as a step-down transformer.
Reason (R): A transformer works only in one direction.
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Answer

(b) :Both A and R are true but R is not the correct explanation of A.
Explanation: Step-up transformer cannot be used as a step down transformer or vice versa. The assertion is true. So, the transformer is a uni-directional device. The reason is also true. But the reason does not explain the assertion.

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