A flag is waved underwater at a depth of 1.2 m below the surface. An observer at the edge of the water observes the flag to be at what depth? Let the indices of refraction nwater = 1.33 and nair = 1.00. 0.90 cm
1.6 cm
1.2 cm
0.78 cm

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 =