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A spherical black body of 10 cm radius at 327degree celcies what is the power |
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Answer» As we learnt inRadiant POWER (P) -P=frac{Q}{t}=Aepsilon sigma heta^{4}- Power of radiation is P=\sigma A T^{4} (For blackbody)\frac{P_{2}}{P_{1}}=\left(\frac{A_{2}}{A_{1}} \right ).\left(\frac{T_{2}}{T_{1}} \right )^{4}=\left(\frac{r_{2}}{r_{1}} \right )^{2}.\left(\frac{T_{2}}{T_{1}} \right )^{4}ACCORDING to question\frac{r_{2}}{r_{1}}=\frac{1}{2}\ \: \: \: and\ \: \: \: \frac{T_{2}}{T_{1}}=2THEN \frac{P_{2}}{P_{1}}=\left(\frac{1}{2} \right )^{2}.2^{4}=2^{2}or P2 = 4P1 = 4 \times 450 W = 1800 WCorrect OPTION is 4. Option 1)225IncorrectOption 2)450IncorrectOption 3)1000 |
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