If a 65kg skydiver jumps out of an airplane at a height of 1200m, what is the fastest they could be traveling when they reach a height of 400m? At that height, they are falling at a speed of 53m/s. How much energy did they transfer to air molecules?

Avertical clean glass piezometer tube has an inside diameter of d = 1 mm and is used to measure pressure in a horizontal pipe carrying water as shown. due to pressure in the pipe, the water at 20c rises into the tube to a height h. if the water pressure in the pipe is p = 500 pa gauge, estimate the height h: (a) without considering surface tension (b) with surface tension (capillary) effects. the contact angle  can be assumed at 30 deg