A solid cylindrical copper rod of length 0.25m is meant to conduct 1.0×103W of thermal energy from an engine block at 200∘C to a coolant reservoir at 50∘C. Spatial constraints limit the rod’s diameter to no more than 1.5cm. Copper has thermal conductivity 400W/(m⋅∘C). Which statement correctly describes whether the design goal is achievable and, if not, what diameter would be required?
a) No; the rod would need a diameter of roughly 3.6cm to conduct the required power.
b) Yes; the goal is achievable with the maximum allowed diameter of 1.5cm.
c) No; the rod would need a diameter of roughly 7.3cm to conduct the required power.
d) No; the rod would need a diameter of roughly 14.6cm to conduct the required power.