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MODEL PAPER 10 — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsMODEL PAPER 101 Mark
MCQ
Assertion (A):  An alternating current of frequency 50 Hz becomes zero, 100 times in one second. 
Reason (R): Alternating current changes direction and becomes zero twice in a cycle.
  • 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

(b)Both A and R are true but R is not the correct explanation of A.
Explanation: Both A and R are true and R is the correct explanation of A.

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