Answer Happy

1. Dimensional Analysis / Order-of-Magnitude (24 points): a. Use dimensional analysis to derive a formula for the terminal velocity (i.e., velocity at which gravity balances air resistance) for any object, e.g., a sky-diving human being. [Hint: refer back to your solution for the homework problem about flying around the world, or search for the solution and use that as a guide for what quantities are relevant; remember to cite your sources if so]. b. Using your formula above, estimate the terminal velocity for a falling structural bolt, weighing 100g and with a surface area of 4 cm?. C. Calculate the kinetic energy of a bolt falling at terminal velocity. Is this higher or lower than the energy required to fracture a skull? (50-60J). d. Using order-of-magnitude reasoning, about how many lives per year are saved by people wearing hard hats at construction sites?