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Magnetism And Matter — Physics STD 12 Science — Question

Gujarat 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): Magnetic moment is measured in joule/ tesla or amp m2.
Reason (R): Joule/ tesla is equivalent to amp m2.
✓

Answer

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

Explanation:

Magnetic moment $=\frac{\text{joule}}{\text{tesla}}=\frac{\text{W}}{\text{B}}=\frac{\text{W}}{\text{F\ qv}}$

$=\frac{\text{Wqv}}{\text{F}}=\frac{[\text{MF}^2\text{T}^{-2}][\text{AT}[\text{LT}^{-1}]]}{[\text{MLT}^{-2}]}$

$=[\text{AL}^2]=\text{amp m}^2$

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