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MODEL PAPER 6 — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMODEL PAPER 61 Mark
MCQ
Assertion (A): Transformers are used only in alternating current sources, not in direct current.
Reasons (R): Only a.c. can be stepped up or down by means of transformers.
  • A
    Both A and R are true and R is the correct explanation of A.
  • B
    Both A and R are true but R is not the correct explanation of A.
  • C
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

(a) Both A and R are true and R is the correct explanation of A.
Explanation: A transformer works on the principle of mutual induction. It can step up or step down a changing current like a.c. and not d.c

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