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A physical quantity is defined as X = L^x C^y R^z , where L , C , and R are self-inductance, capacitance, and resistance respectively, and x, y, z are non-zero real numbers. If X is found to be entirely independent of the fundamental dimension of electric current [A] , what must be true about its dependence on the dimensions of mass [M] and length [L] ?

Options

  1. AX depends on both mass and length.
  2. BX is independent of both mass and length.
  3. CX depends on mass but is independent of length.
  4. DX depends on length but is independent of mass.

Correct answer

B. X is independent of both mass and length.

Step-by-step solution

The dimensional formulas for the given quantities are: [L] = [M L^2 T⁻² A⁻²] [C] = [M⁻¹ L⁻² T^4 A^2] [R] = [M L^2 T⁻³ A⁻²] For the quantity X = L^x C^y R^z , the combined dimensional formula is: [X] = [M L^2 T⁻² A⁻²]^x [M⁻¹ L⁻² T^4 A^2]^y [M L^2 T⁻³ A⁻²]^z Grouping the fundamental dimensions: [X] = [M^ x - y + z L^ 2x - 2y + 2z T^ -2x + 4y - 3z A^ -2x + 2y - 2z ] It is given that X is independent of the dimension of electric current [A] . Therefore, the exponent of A must be zero: -2x + 2y - 2z = 0 y = x + z Now, s

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