Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Units and Measurements question

2025 · 4 Apr · Shift 2 · Q56
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Units and Measurements
  5. /2025 · 4 Apr · Shift 2 · Q56

Units and Measurements question

2025 · 4 Apr · Shift 2 · Q56

JEE MainPhysicsUnits and MeasurementsMCQ+4 / −1
In an electromagnetic system, a quantity defined as the ratio of electric dipole moment and magnetic dipole moment has dimension of [MPLQTRAS]\left[\mathrm{M}^{\mathrm{P}} \mathrm{L}^{\mathrm{Q}} \mathrm{T}^R A^{\mathrm{S}}\right][MPLQTRAS]. The value of P and Q are :
  1. A
    −1,0-1,0−1,0
  2. B
    0,−10,-10,−1
  3. C
    −1,1-1,1−1,1
  4. D
    1,−11,-11,−1
View written solutionFree

Correct answer: B

  1. Write dimensions of electric dipole moment

Electric dipole moment is p=qℓp = q\ellp=qℓ where charge qqq has dimension [q]=[AT][q] = [AT][q]=[AT] and length has dimension [L][L][L].

So, [p]=[AT] [L]=[ALT][p] = [AT]\,[L] = [AL T][p]=[AT][L]=[ALT]

  1. Write dimensions of magnetic dipole moment

Magnetic dipole moment is m=I×aream = I \times \text{area}m=I×area Thus, [m]=[A] [L2]=[AL2][m] = [A]\,[L^2] = [A L^2][m]=[A][L2]=[AL2]

  1. Find the ratio

Required quantity is electric dipole momentmagnetic dipole moment\frac{\text{electric dipole moment}}{\text{magnetic dipole moment}}magnetic dipole momentelectric dipole moment​ So its dimensions are [ALT][AL2]=[L−1T]\frac{[ALT]}{[AL^2]} = [L^{-1}T][AL2][ALT]​=[L−1T]

Hence, [MPLQTRAS]=[M0L−1T1A0][M^P L^Q T^R A^S] = [M^0 L^{-1} T^1 A^0][MPLQTRAS]=[M0L−1T1A0]

Therefore, P=0,Q=−1P=0,\quad Q=-1P=0,Q=−1

  1. Match with options

This corresponds to Option B.

PreviousNext

More from Units and Measurements

  • For the determination of refractive index of glass slab, a travelling microscope is used whose main scale contains 300 equal divisions equals to 15 cm . The vernier scale attached to the microscope has 25 divisions equals to 24 divisions…2025 · MCQ
  • The dimension of ϵ0​μ0​​​ is equal to that of: (μ0​ = Vacuum permeability and ϵ0​ = Vacuum permittivity)2025 · MCQ
  • Match List - I with List - II. Choose the correct answer from the options given below : Includes table2025 · MCQ
  • A quantity Q is formulated as X−2Y+23​Z−52​. X, Y, and Z are independent parameters which have fractional errors of 0.1, 0.2, and 0.5, respectively in measurement. The maximum fractional error of Q is2025 · MCQ
  • If B is magnetic field and μ0​ is permeability of free space, then the dimensions of (B/μ0​) is2025 · MCQ
  • Given below are two statements : Statement I: In a vernier callipers, one vernier scale division is always smaller than one main scale division. Statement II : The vernier constant is given by one main scale division multiplied by the…2025 · MCQ
  • The maximum percentage error in the measurment of density of a wire is [Given, mass of wire =(0.60±0.003)g radius of wire =(0.50±0.01)cm length of wire =(10.00±0.05)cm]2025 · MCQ
  • The position of a particle moving on x-axis is given by x(t)=Asint+Bcos2t+Ct2+D, where t is time. The dimension of DABC​ is2025 · MCQ