14.60. Set Up: A blackbody has Solve: (a) (b) 14.61. Set Up: (a) and (b) and (c) In T must be in kelvins. Solve: (a) (b) (c) (d) The surface area of a sphere is use this for your head. Treat each arm, each leg and your trunk as cylinders; the surface area of a cylinder of radius r and length l is Should you include the area of each end of the cylinders? Reflect: Since the radiation heat current is proportional to the net rate of heat loss increases rapidly when the air temperature decreases. 14.62. Set Up: The surface area of a sphere of radius r is Apply and solve for A . Solve: gives gives The diameter is The radius we calcu-lated is in excellent agreement with the value given in Appendix F. 14.63. Set Up: In the radiation equation the temperatures must be in kelvins; and Call the basal metabolic rate BMR. Solve: (a) (b) so 14.64. Set Up: The surface area of a sphere is Solve: 14.65. Set Up and Solve: Reflect: Even though the filament is small, its coil shape gives it a relatively large surface area. 14.66. Set Up:
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