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Calculate the energy radiated per minute...

Calculate the energy radiated per minute by a black body of surface area `200 cm^(2)` , maintained at `127^(@)`C. `sigma = 5.7xx10^(-8)Wm^(-2)K^(-4)`

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To solve the problem of calculating the energy radiated per minute by a black body of surface area \(200 \, \text{cm}^2\) maintained at \(127^\circ C\), we will use Stefan-Boltzmann Law, which states that the power radiated by a black body is given by: \[ P = \sigma A T^4 \] where: - \(P\) is the power (energy per second) in watts (J/s), - \(\sigma\) is the Stefan-Boltzmann constant (\(5.67 \times 10^{-8} \, \text{W/m}^2\text{K}^4\)), - \(A\) is the surface area in square meters, - \(T\) is the absolute temperature in Kelvin. ### Step-by-Step Solution: 1. **Convert the temperature from Celsius to Kelvin**: \[ T(K) = 127 + 273 = 400 \, K \] 2. **Convert the surface area from cm² to m²**: \[ A = 200 \, \text{cm}^2 = 200 \times 10^{-4} \, \text{m}^2 = 0.02 \, \text{m}^2 \] 3. **Calculate the power radiated using Stefan-Boltzmann Law**: \[ P = \sigma A T^4 \] Substituting the values: \[ P = 5.67 \times 10^{-8} \, \text{W/m}^2\text{K}^4 \times 0.02 \, \text{m}^2 \times (400 \, K)^4 \] 4. **Calculate \(T^4\)**: \[ T^4 = (400)^4 = 256 \times 10^8 \, K^4 \] 5. **Substituting \(T^4\) back into the power equation**: \[ P = 5.67 \times 10^{-8} \times 0.02 \times 256 \times 10^8 \] 6. **Simplifying the equation**: \[ P = 5.67 \times 256 \times 0.02 \] \[ P = 5.67 \times 5.12 = 29.0664 \, \text{W} \] 7. **Calculate the energy radiated per minute**: \[ \text{Energy per minute} = P \times 60 \, \text{s} \] \[ \text{Energy per minute} = 29.0664 \, \text{W} \times 60 \, \text{s} = 1743.984 \, \text{J} \] ### Final Answer: The energy radiated per minute by the black body is approximately \(1744 \, \text{J}\).

To solve the problem of calculating the energy radiated per minute by a black body of surface area \(200 \, \text{cm}^2\) maintained at \(127^\circ C\), we will use Stefan-Boltzmann Law, which states that the power radiated by a black body is given by: \[ P = \sigma A T^4 \] where: - \(P\) is the power (energy per second) in watts (J/s), ...
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