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Moving Charges and Magnetism — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMoving Charges and Magnetism1 Mark
MCQ
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.
Assertion (A): Magnetic moment is measured in joule/ tesla or amp m2. Reason (R): Joule/ tesla is equivalent to amp m2.
  • 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 and R is also false.
✓

Answer

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

Explanation:

Magnetlcmoment $=\frac{\text{joule}}{\text{tesla}}=\frac{\text{w}}{\text{B}}=\frac{\text{W}}{\frac{\text{F}}{\text{qu}}}$

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

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

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