Two parallel disks shown in the figure have emissivity of 0.6. If one of the disks is at 200ºC and the other one is at 30ºC, (a) determine the net heat transfer between the two disks if the surroundings re-radiate heat and (b) determine the net heat transfer between the two disks if the surroundings are a black body at 20ºC.
You might also like to view...
When the sum of the external forces and the sum of the external torques on a body are both zero, we can conclude that
a. the body is moving at constant velocity but is not rotating. b. the body is rotating at constant angular velocity but has no linear velocity. c. the body has neither linear nor angular velocity. d. the body may have constant linear or angular velocity, but not both simultaneously. e. the body may have constant linear or constant angular velocity, or both simultaneously.
Which of the following best describes rain on Venus?
A) It does not have rain. B) It has sulfuric acid rain that causes erosion on the surface. C) It has sulfuric acid rain in its atmosphere, but the drops evaporate before hitting the surface. D) It has liquid water rain that causes erosion on the surface. E) It has liquid water rain in its atmosphere, but the drops evaporate before hitting the surface.
Explain why it is so difficult to see planets around other stars
What will be an ideal response?
A star begins fusing hydrogen to helium the moment it leaves the main sequence
Indicate whether the statement is true or false