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Magnetism And Matter — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsMagnetism And Matter1 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): At neutral point, a compass needle point out in any arbitrary direction.
Reason (R): Magnetic field of earth is balanced by field due to magnets at the neutral points.
✓

Answer

  1. Both A and R are true and R is the correct explanation of A.
Explanation:
A neutral point in the magnetic field of a bar magnet is that point, where the field due to magnet is completely neutralised by the horizontal component of earth's magnetic field. The net horizontal field is zero at such a point. If a compass needle is placed at such a point, it can stay in any position.

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