Heat Transfer Exam 1-Questions and Answers Graded A+

Heat Transfer Exam 1-Questions and Answers Graded A+ When there is a constant heat generation qdot in a slab or plane wall with thermal conductivity k, what statement is CORRECT? Assume one-directional (x-direction) steady-state conduction. A. temperature T is linear. B. d^2T/dx^2=-qdot/k C. dT/dx=const D.heat transfer rate across the wall q is a constant. - ANSWER-B. d^2T/dx^2=-qdot/k Cont... if the boundary conditions at the two sides of the wall are the same, where would be the maximum temperature take place? A. the left or the right side of the wall. B. the center-line of the wall. C. cannot be determined. - ANSWER-B. the center-line of the wall. cont... if the boundary conditions at the two sides of the wall are NOT the same, what statement is CORRECT regarding where the maximum temperature would take place? A. at a location where heat flux is zero. B. at a location where d^2T/dx^2=0 C. at the center of the wall - ANSWER-A. at a location where heat flux is zero A long solid rod of diameter D has a uniform heat generation of qdot. What is the appropriate solution of temperature T(r) at steady state? A. -(qdot/(4k))r^2+c1/r +c2 B. -(qdot/(4k))r^2+c2 C. -(qdot/(4k))r^2+c1 ln(r) - ANSWER-B. -(qdot/(4k))r^2+c2 Cont... where is the maximum temperature inside the rod? A. the surface of the rod. B. the midpoint of the rod. C. the centerline of the rod. - ANSWER-C. the centerline of the rod. Cont... If the rod surface temperature is Ts, what is the maximum temperature inside the rod? A. Ts+D^2(qdot)/(4k) B. Ts+D^2(qdot)/(6k) C. Ts+D^2(qdot)/(8k) D. Ts+D^2(qdot)/(16k) - ANSWER-D. Ts+D^2(qdot)/(16k) Cont... What is the thermal conduction resistance per unit length? A. ln(D/2)/(2 pi k) B. ln(D)/(2 pi k) C. Not defined because qdot is not zero. - ANSWER-c. Not defined because qdot is not zero.