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A small hole is made in a hollow enclosu...

A small hole is made in a hollow enclosure whose walls are maintained at a temperature of 1000 K. The amount of energy being emitted per square metre per second is :

A

567 J

B

5670 J

C

56700 J

D

567000 J

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The correct Answer is:
To solve the problem of finding the amount of energy emitted per square meter per second from a small hole in a hollow enclosure at a temperature of 1000 K, we can use Stefan-Boltzmann Law. Here’s a step-by-step solution: ### Step 1: Understand the Concept The energy emitted per unit area per second (intensity) from a black body is given by the Stefan-Boltzmann Law: \[ I = \sigma T^4 \] where: - \( I \) is the intensity (energy emitted per square meter per second), - \( \sigma \) is the Stefan-Boltzmann constant (\( 5.67 \times 10^{-8} \, \text{W/m}^2\text{K}^4 \)), - \( T \) is the absolute temperature in Kelvin. ### Step 2: Identify Given Values From the problem, we have: - Temperature, \( T = 1000 \, \text{K} \). ### Step 3: Substitute the Values into the Formula Now, we can substitute the values into the Stefan-Boltzmann Law: \[ I = \sigma T^4 \] \[ I = 5.67 \times 10^{-8} \times (1000)^4 \] ### Step 4: Calculate \( T^4 \) Calculate \( (1000)^4 \): \[ (1000)^4 = 10^{12} \] ### Step 5: Substitute \( T^4 \) Back into the Equation Now substitute \( 10^{12} \) back into the equation: \[ I = 5.67 \times 10^{-8} \times 10^{12} \] ### Step 6: Perform the Multiplication Now perform the multiplication: \[ I = 5.67 \times 10^{4} \, \text{W/m}^2 \] ### Step 7: Convert to Joules Since \( 1 \, \text{W} = 1 \, \text{J/s} \), we can express this as: \[ I = 56700 \, \text{J/m}^2\text{s} \] ### Step 8: State the Final Answer Thus, the amount of energy emitted per square meter per second is: \[ \boxed{56700 \, \text{J/m}^2\text{s}} \]

To solve the problem of finding the amount of energy emitted per square meter per second from a small hole in a hollow enclosure at a temperature of 1000 K, we can use Stefan-Boltzmann Law. Here’s a step-by-step solution: ### Step 1: Understand the Concept The energy emitted per unit area per second (intensity) from a black body is given by the Stefan-Boltzmann Law: \[ I = \sigma T^4 \] where: - \( I \) is the intensity (energy emitted per square meter per second), - \( \sigma \) is the Stefan-Boltzmann constant (\( 5.67 \times 10^{-8} \, \text{W/m}^2\text{K}^4 \)), ...
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