A nanowire is a (nearly) one-dimensional structure with a diameter on the order of a few nanometers. Suppose a 137.0-nm-long nanowire made of pure silicon (density of Si = 2.33 g/cm3) has a diameter of 4.07 nm. This nanowire is attached at the top and hanging down vertically due to the force of gravity.
a) What is the tension at the top?
b) What is the tension in the middle?