NEET
- Exam
- NEET
- Subject
- Physics
- Chapter
- Units and Dimensions
NEET · Physics · Units and Dimensions
Match List-I with List-II, where h , c , k_B , σ_s , b , and T...
Match List-I with List-II, where , , , , , and represent Planck's constant, speed of light, Boltzmann constant, Stefan-Boltzmann constant, Wien's displacement constant, and temperature, respectively.
Choose the correct answer from the options given below:
| List-I | List-II |
|---|---|
| A. | I. |
| B. | II. |
| C. | III. |
| D. | IV. |
Choose the correct answer from the options given below:
Options
- AA-IV, B-I, C-II, D-III
- BA-IV, B-II, C-I, D-III
- CA-III, B-I, C-II, D-IV
- DA-II, B-IV, C-I, D-III
Correct answer
A. A-IV, B-I, C-II, D-III
Step-by-step solution
Let us find the dimensional formula for each expression in List-I.
A. :
\left[\dfrac{h c}{k_B T}\right] = \dfrac{[\text{M}\text{L}^3\text{T}^{-2}]}{[\text{M}\text{L}^2\text{T}^{-2}]} = [\text{L}]\dfrac{\sigma_s T^4}{c}[\sigma_s T^4] = \text{Power per unit area} = \dfrac{[\text{M}\text{L}^2\text{T}^{-3}]}{[\text{L}^2]} = [\text{M}\text{T}^{-3}][c] = [\text{L}\text{T}^{-1}] (Matches I)
C. :
\left[\dfrac{b k_B}{h}\right] = \dfrac{[\text{M}\text{L}^3\text{T}^{-2}]}{[\text{M}\text{L}^2\text{T}^{-1}]} = [\text{L}\text{T}^{-1}]\dfrac{\sigma_s b^4}{h c^2}[\sigma_s] = [\text{M}\text{T}^{-3}\text{K}^{-4}][b^4] = [\text{L}^4\text{K}^4][\sigma_s b^4] = [\text{M}\text{L}^4\text{T}^{-3}][h c^2] = [\text{M}\text{L}^2\text{T}^{-1}] \times [\text{L}^2\text{T}^{-2}] = [\text{M}\text{L}^4\text{T}^{-3}] (Matches III)
Therefore, the correct matching is A-IV, B-I, C-II, D-III.
Answer: A-IV, B-I, C-II, D-III
A. :
\left[\dfrac{h c}{k_B T}\right] = \dfrac{[\text{M}\text{L}^3\text{T}^{-2}]}{[\text{M}\text{L}^2\text{T}^{-2}]} = [\text{L}]\dfrac{\sigma_s T^4}{c}[\sigma_s T^4] = \text{Power per unit area} = \dfrac{[\text{M}\text{L}^2\text{T}^{-3}]}{[\text{L}^2]} = [\text{M}\text{T}^{-3}][c] = [\text{L}\text{T}^{-1}] (Matches I)
C. :
\left[\dfrac{b k_B}{h}\right] = \dfrac{[\text{M}\text{L}^3\text{T}^{-2}]}{[\text{M}\text{L}^2\text{T}^{-1}]} = [\text{L}\text{T}^{-1}]\dfrac{\sigma_s b^4}{h c^2}[\sigma_s] = [\text{M}\text{T}^{-3}\text{K}^{-4}][b^4] = [\text{L}^4\text{K}^4][\sigma_s b^4] = [\text{M}\text{L}^4\text{T}^{-3}][h c^2] = [\text{M}\text{L}^2\text{T}^{-1}] \times [\text{L}^2\text{T}^{-2}] = [\text{M}\text{L}^4\text{T}^{-3}] (Matches III)
Therefore, the correct matching is A-IV, B-I, C-II, D-III.
Answer: A-IV, B-I, C-II, D-III