A solid cylinder of radius r_(1) = 2.5cm , length h_(1) = 5.5cm, emissivity 0.85, and temperature 30^(@)C is suspended in an environment of temperature 50^(@)C. (a) What is the cylinder's net thermal radiation transfer rate P_(1) ? (b) If the cylinder is stretched until its radius is r_(2) = 0.50 cm , its net thermal radiation transfer rate becomes P_(2). What is the ratio P_(2)//P_(1) ?

A solid cylinder of radius r_(1) = 2.5cm , length h_(1) = 5.5cm, emiss

1.	A solid cylinder of radius r_(1) = 2.5cm , length h_(1) = 5.5cm, emissivity 0.85, and temperature 30^(@)C is suspended in an environment of temperature 50^(@)C. (a) What is the cylinder's net thermal radiation transfer rate P_(1) ? (b) If the cylinder is stretched until its radius is r_(2) = 0.50 cm , its net thermal radiation transfer rate becomes P_(2). What is the ratio P_(2)//P_(1) ?
Answer» ANSWER :(a) 1.5 W; (B) 3.45

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