A black body with an initial temperature of `300^(@)`C is allowed to cool inside an evacuated enclosure surrounded by melting ice at the rate of `0.35^(@)`C per second. If the mass, specific heat and surface area of the body are 32gm, `420 J kg^(-1)K^(-1)` and `8 cm^(2)` respectively, calculate the stefan's constant.

Explanation

To solve the problem, we will follow these steps:

### Step 1: Understand the given data
- Initial temperature of the black body, \( T_0 = 300^\circ C = 300 + 273 = 573 K \)
- Rate of cooling, \( \frac{\Delta \theta}{\Delta t} = 0.35^\circ C/s = 0.35 K/s \)
- Mass of the body, \( m = 32 g = 0.032 kg \)
- Specific heat, \( C = 420 J/(kg \cdot K) \)
- Surface area, \( A = 8 cm^2 = 8 \times 10^{-4} m^2 \)
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