You place a fireplace poker into the coals of a hot fire (500 degrees c). the poker is made of steel, 50cm long with a diameter of 1.5cm. a) if the other end of the rod is maintained at 31 degrees c, what heat current exists in the rod? b) how long does it take to transfer 10 kj of thermal energy? c) how would the answer to b change if the rod was copper?

Which accurately compares concave and convex lenses?

Which governments provide garbage collection services to homes and businesses

Consider the growth of a 20-nm-diameter silicon nanowire onto a silicon wafer. the temperature of the wafer surface is maintained at 2400 k. assume the thermal conductivity of the silicon nanowire is 20 wm-1k-1 and all its surfaces including the tip are subjected to convection heat transfer with the coefficient h = 1×105 wm-2k-1 and t∞ = 8000 k. when the nanowire grows to l = 300 nm, what is the temperature of the nanowire tip (t (x =