Trini has finished preschool for the day and her dad has come with a surprise. He has tied a 1.80 m rope to a cart to give her a spin in the cart (during which the rope is parallel to the ground). Together, Trini and the cart have a combined mass of 24 kg. Trini's 2 kg backpack is behind her in the cart. The friction between the wheels of the cart and the ground is negligible.

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 =