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BVP Medical BVP Medical Solved Paper-2002

  • question_answer
    A sphere of 3 cm radius acts like a black body. If it is an equilibrium with its surroundings and absorb 30kW of energy radiated to it from the surroundings. Then the temperature of the sphere will be :

    A) 816                                        

    B)  916

    C) 1616                                      

    D)  2615

    Correct Answer: D

    Solution :

                    Energy absorbed by the black body  \[E=\sigma A{{T}^{4}}\] \[30kW=5.672\times {{10}^{-8}}\times 4\pi {{(3\times {{10}^{-2}})}^{2}}{{T}^{4}}\] \[30\times {{10}^{3}}=5.672\times {{10}^{-8}}\times 4\pi \times 9\times {{10}^{-4}}\times {{T}^{4}}\] \[{{T}^{4}}=\frac{30\times {{10}^{3}}}{5.672\times {{10}^{-8}}\times 4\pi \times 9\times {{10}^{-4}}}\] \[=46.875\times {{10}^{12}}\] \[T=2.615\times {{10}^{3}}=2615K\]


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