Isaac throws an apple straight down from a tree with an initial speed of 5.0 \dfrac{\text m}{\text s}5.0 s m 5, point, 0, start fraction, start text, m, end text, divided by, start text, s, end text, end fraction. It hits the ground with a final speed of 12 \dfrac{\text m}{\text s}12 s m 12, start fraction, start text, m, end text, divided by, start text, s, end text, end fraction. How many seconds did the apple fall?

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 =