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Moving Charges and Magnetism — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsMoving Charges and Magnetism1 Mark
Question
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion (A): In electric circuits, wires carrying currents in opposite directions are often twisted together.
Reason (R): If the wire are not twisted together, the combination of the wires forms a current loop. 'Tile magnetic field generated by the loop might affect adjacent circuits or components.
✓

Answer

  1. Both A and R are true and R is the correct explanation of A.

Explanation:

If the wires are twisted together, they can be modelled as a single wire carrying current in the opposite directions. In this model, no magnetic field is induced in the wires which does not affect adjacent circuits.

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