JEE Challenger
More from Units and Measurements

Match Physical Quantities with Dimensional Formulas for Constants

Match List - I with List - II.

List - IList - IIA. Boltzmann constantI.[M1L3T2]B. Stefan’s constantII.[ML2T1]C. Planck’s constantIII.[ML2T2K1]D. Gravitational constantIV.[ML0T3K4]\begin{array}{ll} \text{List - I} & \text{List - II} \\ A. \text{ Boltzmann constant} & I. [M^{-1}L^3T^{-2}] \\ B. \text{ Stefan's constant} & II. [ML^2T^{-1}] \\ C. \text{ Planck's constant} & III. [ML^2T^{-2}K^{-1}] \\ D. \text{ Gravitational constant} & IV. [ML^0T^{-3}K^{-4}] \end{array}

Choose the correct answer from the options given below :

Options

A

A-I, B-II, C-III, D-IV

B

A-IV, B-III, C-II, D-I

C

A-III, B-IV, C-II, D-I

Correct
D

A-II, B-I, C-IV, D-III

Topics & Concepts

Step-by-Step Solution

To find the correct match between the physical constants in List - I and their corresponding dimensional formulas in List - II, we determine the dimensions of each constant using their fundamental physical equations:

  1. Boltzmann Constant (kBk_B): The thermal energy EE is related to absolute temperature TT by the formula: E=kBT    kB=ETE = k_B T \implies k_B = \frac{E}{T}

    Substituting the dimensional formulas for Energy ([E]=[ML2T2][E] = [M L^2 T^{-2}]) and Temperature ([T]=[K][T] = [K]): [kB]=[ML2T2][K]=[ML2T2K1][k_B] = \frac{[M L^2 T^{-2}]}{[K]} = [M L^2 T^{-2} K^{-1}]

    Thus, A matches with III.

  2. Stefan's Constant (σ\sigma): According to Stefan-Boltzmann law, the total radiant energy emitted per unit area per unit time (Emissive power) is proportional to the fourth power of absolute temperature: EAt=σT4    σ=EAtT4\frac{E}{A \cdot t} = \sigma T^4 \implies \sigma = \frac{E}{A \cdot t \cdot T^4}

    Substituting the dimensions of Energy ([E]=[ML2T2][E] = [M L^2 T^{-2}]), Area ([A]=[L2][A] = [L^2]), Time ([t]=[T][t] = [T]), and Temperature ([T]=[K][T] = [K]): [σ]=[ML2T2][L2][T][K4]=[ML0T3K4][\sigma] = \frac{[M L^2 T^{-2}]}{[L^2] [T] [K^4]} = [M L^0 T^{-3} K^{-4}]

    Thus, B matches with IV.

  3. Planck's Constant (hh): The energy EE of a photon is related to its frequency ν\nu by: E=hν    h=EνE = h \nu \implies h = \frac{E}{\nu}

    Substituting the dimensions of Energy ([E]=[ML2T2][E] = [M L^2 T^{-2}]) and Frequency ([ν]=[T1][\nu] = [T^{-1}]): [h]=[ML2T2][T1]=[ML2T1][h] = \frac{[M L^2 T^{-2}]}{[T^{-1}]} = [M L^2 T^{-1}]

    Thus, C matches with II.

  4. Gravitational Constant (GG): According to Newton's law of gravitation, the force between two masses m1m_1 and m2m_2 separated by a distance rr is: F=Gm1m2r2    G=Fr2m1m2F = G \frac{m_1 m_2}{r^2} \implies G = \frac{F r^2}{m_1 m_2}

    Substituting the dimensions of Force ([F]=[MLT2][F] = [M L T^{-2}]), Distance ([r]=[L][r] = [L]), and Mass ([m]=[M][m] = [M]): [G]=[MLT2][L2][M]2=[M1L3T2][G] = \frac{[M L T^{-2}] [L^2]}{[M]^2} = [M^{-1} L^3 T^{-2}]

    Thus, D matches with I.

Comparing with the given choices: A - III, B - IV, C - II, D - I\text{A - III, B - IV, C - II, D - I}

Hence, the correct option is C.

Match Physical Quantities with Dimensional Formulas for Constants | Physics PYQ Solution - JEE Challenger