MCQ
In MKS system, Stefan's constant is denoted by $\sigma$. In CGS system multiplying factor of $\sigma$ will be
- A1
- ✓$10^3$
- C$10^5$
- D$10^2$
✓
Answer
Correct option: B.
$10^3$
(b)
In M.K.S. system unit of $\sigma \text { is } \frac{\mathrm{J}}{\mathrm{m}^2 \times \sec \times K^4} $
$\Rightarrow = \frac{\mathrm{J}}{\mathrm{m^2\times\sec\times K^4}}=\frac{10^7 \mathrm{erg}}{10^4 \mathrm{~cm}^2 \times \sec \times K^4} $
$=10^3 \frac{\mathrm{erg}}{\mathrm{cm}^2 \times \sec \times K^4}$
In M.K.S. system unit of $\sigma \text { is } \frac{\mathrm{J}}{\mathrm{m}^2 \times \sec \times K^4} $
$\Rightarrow = \frac{\mathrm{J}}{\mathrm{m^2\times\sec\times K^4}}=\frac{10^7 \mathrm{erg}}{10^4 \mathrm{~cm}^2 \times \sec \times K^4} $
$=10^3 \frac{\mathrm{erg}}{\mathrm{cm}^2 \times \sec \times K^4}$
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