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There is a temperature difference of 1K ...

There is a temperature difference of `1K` between two black patches of skin on patient's chest and each patch having area A The radiant heat emitted from them is differ by `2%` then temperature of two patches may be .

A

`100 K, 101K`

B

`300K,301K`

C

`200K,201K`

D

`400K,401K`

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To solve the problem, we will use the Stefan-Boltzmann law, which states that the power radiated by a black body is proportional to the fourth power of its absolute temperature. Let's break down the solution step by step. ### Step 1: Understand the Problem We have two black patches on a patient's chest with a temperature difference of 1 K. The radiant heat emitted from these patches differs by 2%. We need to find the temperatures of these two patches. ### Step 2: Define Variables Let: - \( T_2 \) = temperature of the cooler patch - \( T_1 \) = temperature of the warmer patch - Given that \( T_1 - T_2 = 1 \, K \) ### Step 3: Apply the Stefan-Boltzmann Law According to the Stefan-Boltzmann law, the power radiated by each patch can be expressed as: - \( P_1 = \sigma A T_1^4 \) (for the warmer patch) - \( P_2 = \sigma A T_2^4 \) (for the cooler patch) ### Step 4: Set Up the Power Difference Equation The difference in power radiated is given as: \[ \frac{P_1 - P_2}{P_2} \times 100 = 2\% \] This can be rewritten as: \[ P_1 - P_2 = 0.02 P_2 \] Substituting the expressions for \( P_1 \) and \( P_2 \): \[ \sigma A T_1^4 - \sigma A T_2^4 = 0.02 \sigma A T_2^4 \] We can cancel \( \sigma A \) from both sides: \[ T_1^4 - T_2^4 = 0.02 T_2^4 \] ### Step 5: Rearrange the Equation Rearranging gives us: \[ T_1^4 = 1.02 T_2^4 \] ### Step 6: Substitute \( T_1 \) in Terms of \( T_2 \) Since \( T_1 = T_2 + 1 \): \[ (T_2 + 1)^4 = 1.02 T_2^4 \] ### Step 7: Expand the Left Side Using the binomial expansion: \[ T_2^4 + 4T_2^3 + 6T_2^2 + 4T_2 + 1 = 1.02 T_2^4 \] Rearranging gives: \[ 0.02 T_2^4 - 4T_2^3 - 6T_2^2 - 4T_2 - 1 = 0 \] ### Step 8: Solve the Polynomial This is a polynomial equation in \( T_2 \). Solving this numerically or using approximation methods will yield the value of \( T_2 \). ### Step 9: Find \( T_1 \) Once \( T_2 \) is found, use \( T_1 = T_2 + 1 \) to find \( T_1 \). ### Final Step: Calculate and State the Answer After solving the polynomial, we find: - \( T_2 \approx 200 \, K \) - \( T_1 \approx 201 \, K \) Thus, the temperatures of the patches are: - \( T_1 = 201 \, K \) - \( T_2 = 200 \, K \)

To solve the problem, we will use the Stefan-Boltzmann law, which states that the power radiated by a black body is proportional to the fourth power of its absolute temperature. Let's break down the solution step by step. ### Step 1: Understand the Problem We have two black patches on a patient's chest with a temperature difference of 1 K. The radiant heat emitted from these patches differs by 2%. We need to find the temperatures of these two patches. ### Step 2: Define Variables Let: - \( T_2 \) = temperature of the cooler patch ...
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