. A man throws a stone vertically downward with an initial speed of 12.0 m/s from the roof of a building, 30.0 m
above the ground. (a) How long does it take the stone to
reach the ground? (b) What is the speed of the stone at
impact?

Abeverage can is made of 3004-h19 aluminum alloy (elastic modulus 69 gpa, tensile yield strength 285 mpa, density 2.72 g/cm^3). the dimensions on the can are approximated as a thin-walled cylinder with a height of 4.83 inches, diameter of 2.60 inches. empty the can has a mass of 14.2 g. determine: a. the wall thickness of the cylinder b. assuming a pinned-pinned condition what is the critical load? c. assuming a fixed-fixed condition what is the critical load?